Equation form expr-0022ffa6a3f66313
Read as: m is less than k
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: m is less than k
Turing machines
Read as: m is less than k
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: m is less than k
Read as: k plus one
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: k plus one
Read as: and
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: and
Read as: object language symbol zero
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol zero
Read as: s
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: s
Read as: capital sigma prime equals the set containing the left end marker, the blank symbol, and A
Means: An explicit finite-set expression or equation that preserves the source braces as set enclosure. Read as: capital sigma prime equals the set containing the left end marker, the blank symbol, and A.
Read as: object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for n close parenthesis
Read as: the interpretation of the less-than relation in structure M double prime equals the set containing the tuple zero comma one, the tuple one comma one, and the tuple two comma two
Means: An explicit finite-set expression or equation that preserves the source braces as set enclosure. Read as: the interpretation of the less-than relation in structure M double prime equals the set containing the tuple zero comma one, the tuple one comma one, and the tuple two comma two.
Read as: object language symbol S sub sigma sub i open parenthesis the numeral for i comma the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol S sub sigma sub i open parenthesis the numeral for i comma the numeral for n close parenthesis
Read as: M
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: M
Read as: m equals k
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: m equals k
Read as: the numeral for k
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the numeral for k
Read as: T prime open parenthesis M comma w close parenthesis semantically entails C open parenthesis M comma w comma n close parenthesis and formula B open parenthesis the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T prime open parenthesis M comma w close parenthesis semantically entails C open parenthesis M comma w comma n close parenthesis and formula B open parenthesis the numeral for n close parenthesis
Read as: object language symbol S sub left end marker open parenthesis the numeral for zero comma the numeral for zero close parenthesis and object language symbol S sub sigma sub i sub one open parenthesis the numeral for one comma the numeral for zero close parenthesis and and so on and object language symbol S sub sigma sub i sub k open parenthesis the numeral for k comma the numeral for zero close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol S sub left end marker open parenthesis the numeral for zero comma the numeral for zero close parenthesis and object language symbol S sub sigma sub i sub one open parenthesis the numeral for one comma the numeral for zero close parenthesis and and so on and object language symbol S sub sigma sub i sub k open parenthesis the numeral for k comma the numeral for zero close parenthesis
Read as: sigma sub i
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: sigma sub i
Read as: the interpretation of successor symbol in structure M prime open parenthesis x close parenthesis equals cases begin; row one: x plus one, if x is less than n; row two: n, otherwise comma; cases end
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: the interpretation of successor symbol in structure M prime open parenthesis x close parenthesis equals cases begin; row one: x plus one, if x is less than n; row two: n, otherwise comma; cases end
Read as: delta open parenthesis q comma sigma close parenthesis
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q comma sigma close parenthesis
Read as: n equals zero
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: n equals zero
Read as: x equals y equals n
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: x equals y equals n
Read as: x plus one
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: x plus one
Read as: the numeral for two
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the numeral for two
Read as: d
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: d
Read as: one zero
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: one zero
Read as: n
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: n
Read as: E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: E open parenthesis M comma w close parenthesis
Read as: the interpretation of object language symbol S sub blank symbol in structure M prime prime
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: the interpretation of object language symbol S sub blank symbol in structure M prime prime
Read as: object language symbol Q sub q open parenthesis x comma y close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol Q sub q open parenthesis x comma y close parenthesis
Read as: n plus one
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: n plus one
Read as: E concatenated with D
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: E concatenated with D
Read as: T open parenthesis M comma w close parenthesis proves the numeral for k is less than the numeral for k prime
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: T open parenthesis M comma w close parenthesis proves the numeral for k is less than the numeral for k prime
Read as: structure M
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M
Read as: move right
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: move right
Read as: y prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: y prime
Read as: the numeral for zero equals object language symbol zero next row the numeral for n plus one equals the numeral for n prime
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: the numeral for zero equals object language symbol zero next row the numeral for n plus one equals the numeral for n prime
Read as: T open parenthesis M comma w close parenthesis semantically entails E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis semantically entails E open parenthesis M comma w close parenthesis
Read as: not
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: not
Read as: Right move induction display. For every x and y, if the machine is in state q scanning square x and that square contains sigma at time y, then at time y prime it is in state q prime scanning square x prime, writes sigma prime at x, and leaves every other square unchanged. Instantiate x with numeral m and y with numeral n. Combine this transition with the represented current configuration to obtain state q prime at square m prime and time n prime, the updated symbol at square m, all unchanged listed tape symbols, and a blank tail beyond numeral k
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: Right move induction display. For every x and y, if the machine is in state q scanning square x and that square contains sigma at time y, then at time y prime it is in state q prime scanning square x prime, writes sigma prime at x, and leaves every other square unchanged. Instantiate x with numeral m and y with numeral n. Combine this transition with the represented current configuration to obtain state q prime at square m prime and time n prime, the updated symbol at square m, all unchanged listed tape symbols, and a blank tail beyond numeral k
Read as: k is less than n
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: k is less than n
Read as: w equals sigma sub i sub one and so on sigma sub i sub k
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: w equals sigma sub i sub one and so on sigma sub i sub k
Read as: h open parenthesis e comma n close parenthesis equals cases begin; row one: zero, if machine M sub e does not halt for input n; row two: one, if machine M sub e halts for input n; cases end
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: h open parenthesis e comma n close parenthesis equals cases begin; row one: zero, if machine M sub e does not halt for input n; row two: one, if machine M sub e halts for input n; cases end
Read as: x
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: x
Read as: E open parenthesis M comma the empty sequence code close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: E open parenthesis M comma the empty sequence code close parenthesis
Read as: q sub i
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: q sub i
Read as: the numeral for k is less than the numeral for k prime
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: the numeral for k is less than the numeral for k prime
Read as: stay put
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: stay put
Read as: T open parenthesis M comma w close parenthesis proves the numeral for m is less than the numeral for k
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: T open parenthesis M comma w close parenthesis proves the numeral for m is less than the numeral for k
Read as: object language symbol S sub sigma open parenthesis x comma y close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol S sub sigma open parenthesis x comma y close parenthesis
Read as: object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for n close parenthesis
Read as: the domain of structure M
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the domain of structure M
Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x prime comma y close parenthesis and object language symbol S sub sigma open parenthesis x prime comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x prime comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis close parenthesis close parenthesis and next row then for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis the numeral for zero comma y close parenthesis and object language symbol S sub sigma open parenthesis the numeral for zero comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis the numeral for zero comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis the numeral for zero comma y prime close parenthesis and formula A open parenthesis the numeral for zero comma y close parenthesis close parenthesis close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x prime comma y close parenthesis and object language symbol S sub sigma open parenthesis x prime comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x prime comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis close parenthesis close parenthesis and next row then for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis the numeral for zero comma y close parenthesis and object language symbol S sub sigma open parenthesis the numeral for zero comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis the numeral for zero comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis the numeral for zero comma y prime close parenthesis and formula A open parenthesis the numeral for zero comma y close parenthesis close parenthesis close parenthesis
Read as: formula A open parenthesis m comma n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: formula A open parenthesis m comma n close parenthesis
Read as: structure M satisfies formula B
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M satisfies formula B
Read as: w equals the empty sequence code
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: w equals the empty sequence code
Read as: object language symbol Q sub q open parenthesis the numeral for m comma the numeral for k close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol Q sub q open parenthesis the numeral for m comma the numeral for k close parenthesis
Read as: structure M prime satisfies T open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M prime satisfies T open parenthesis M comma w close parenthesis
Read as: for every x, open parenthesis the numeral for k is less than x implies object language symbol S sub blank symbol open parenthesis x comma the numeral for n prime close parenthesis close parenthesis
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: for every x, open parenthesis the numeral for k is less than x implies object language symbol S sub blank symbol open parenthesis x comma the numeral for n prime close parenthesis close parenthesis
Read as: delta open parenthesis q sub i comma sigma close parenthesis equals the tuple q sub j comma sigma prime comma stay put
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q sub i comma sigma close parenthesis equals the tuple q sub j comma sigma prime comma stay put
Read as: stroke symbol
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: stroke symbol
Read as: successor symbol
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: successor symbol
Read as: D
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: D
Read as: e
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: e
Read as: formula B open parenthesis y prime close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: formula B open parenthesis y prime close parenthesis
Read as: for every x, x is less than x prime
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: for every x, x is less than x prime
Read as: S concatenated with J
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: S concatenated with J
Read as: Q times capital sigma
Means: Notation for a machine prime s state set, tape alphabet, or defining tuple. Read as: Q times capital sigma
Read as: semantically entails T open parenthesis M comma w close parenthesis implies E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: semantically entails T open parenthesis M comma w close parenthesis implies E open parenthesis M comma w close parenthesis
Read as: structure M
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M
Read as: the tuple x comma y is in the interpretation of is less than in structure M prime
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: the tuple x comma y is in the interpretation of is less than in structure M prime
Read as: T open parenthesis M comma w close parenthesis semantically entails C open parenthesis M comma w comma n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis semantically entails C open parenthesis M comma w comma n close parenthesis
Read as: H
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: H
Read as: s prime open parenthesis e close parenthesis equals cases begin; row one: one, if machine M sub e halts for input e; row two: undefined, if machine M sub e does not halt for input e; cases end
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: s prime open parenthesis e close parenthesis equals cases begin; row one: one, if machine M sub e halts for input e; row two: undefined, if machine M sub e does not halt for input e; cases end
Read as: the set containing s and h
Means: An explicit finite-set expression or equation that preserves the source braces as set enclosure. Read as: the set containing s and h.
Read as: E concatenated with D
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: E concatenated with D
Read as: f open parenthesis e comma n close parenthesis equals m
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: f open parenthesis e comma n close parenthesis equals m
Read as: f open parenthesis n close parenthesis
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: f open parenthesis n close parenthesis
Read as: Q
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: Q
Read as: X
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: X
Read as: y plus one
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: y plus one
Read as: i is less than m
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: i is less than m
Read as: object language symbol S sub sigma sub m open parenthesis the numeral for m comma the numeral for n prime close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol S sub sigma sub m open parenthesis the numeral for m comma the numeral for n prime close parenthesis
Read as: three
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: three
Read as: semantically entails T open parenthesis M comma w close parenthesis implies E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: semantically entails T open parenthesis M comma w close parenthesis implies E open parenthesis M comma w close parenthesis
Read as: sigma sub one
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: sigma sub one
Read as: w
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: w
Read as: T open parenthesis M sub e comma w close parenthesis implies E open parenthesis M sub e comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M sub e comma w close parenthesis implies E open parenthesis M sub e comma w close parenthesis
Read as: m is less than k
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: m is less than k
Read as: the interpretation of object language symbol Q sub q sub zero in structure M prime prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the interpretation of object language symbol Q sub q sub zero in structure M prime prime
Read as: T open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Read as: the numeral for l is syntactically identical to the numeral for zero
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the numeral for l is syntactically identical to the numeral for zero
Read as: for every z, open parenthesis open parenthesis open parenthesis z is less than x or x is less than z close parenthesis and object language symbol S sub sigma open parenthesis z comma y close parenthesis close parenthesis implies object language symbol S sub sigma open parenthesis z comma y prime close parenthesis close parenthesis
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: for every z, open parenthesis open parenthesis open parenthesis z is less than x or x is less than z close parenthesis and object language symbol S sub sigma open parenthesis z comma y close parenthesis close parenthesis implies object language symbol S sub sigma open parenthesis z comma y prime close parenthesis close parenthesis
Read as: zero is less than or equal to i is less than or equal to k
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: zero is less than or equal to i is less than or equal to k
Read as: capital A symbol
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: capital A symbol
Read as: structure M satisfies object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M satisfies object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis
Read as: object language symbol S sub sigma sub i open parenthesis the numeral for i comma the numeral for n prime close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol S sub sigma sub i open parenthesis the numeral for i comma the numeral for n prime close parenthesis
Read as: n is in the natural numbers
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: n is in the natural numbers
Read as: i is not equal to m
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: i is not equal to m
Read as: s open parenthesis e close parenthesis equals zero
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: s open parenthesis e close parenthesis equals zero
Read as: there exists x, there exists y, object language symbol Q sub h open parenthesis x comma y close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: there exists x, there exists y, object language symbol Q sub h open parenthesis x comma y close parenthesis
Read as: s prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: s prime
Read as: C open parenthesis M comma w comma n close parenthesis semantically entails E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: C open parenthesis M comma w comma n close parenthesis semantically entails E open parenthesis M comma w close parenthesis
Read as: formula B open parenthesis the numeral for n close parenthesis semantically entails the numeral for k is less than the numeral for n implies the numeral for k is not equal to the numeral for n
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: formula B open parenthesis the numeral for n close parenthesis semantically entails the numeral for k is less than the numeral for n implies the numeral for k is not equal to the numeral for n
Read as: zero
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: zero
Read as: for every x, open parenthesis the numeral for k is less than x implies the numeral for m is less than x close parenthesis
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: for every x, open parenthesis the numeral for k is less than x implies the numeral for m is less than x close parenthesis
Read as: f from the natural numbers times the natural numbers partially maps to the natural numbers
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: f from the natural numbers times the natural numbers partially maps to the natural numbers
Read as: m
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: m
Read as: object language symbol zero prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol zero prime
Read as: the domain of structure M double prime equals the set containing zero, one, and two
Means: An explicit finite-set expression or equation that preserves the source braces as set enclosure. Read as: the domain of structure M double prime equals the set containing zero, one, and two.
Read as: object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for k close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for k close parenthesis
Read as: T open parenthesis M comma w close parenthesis implies E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis implies E open parenthesis M comma w close parenthesis
Read as: for every x, open parenthesis the numeral for k prime is less than x implies object language symbol S sub blank symbol open parenthesis x comma the numeral for n prime close parenthesis close parenthesis
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: for every x, open parenthesis the numeral for k prime is less than x implies object language symbol S sub blank symbol open parenthesis x comma the numeral for n prime close parenthesis close parenthesis
Read as: q sub one
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: q sub one
Read as: the interpretation of successor symbol in structure M prime prime open parenthesis two close parenthesis equals two
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: the interpretation of successor symbol in structure M prime prime open parenthesis two close parenthesis equals two
Read as: one
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: one
Read as: T open parenthesis M comma the empty sequence code close parenthesis and E open parenthesis M comma the empty sequence code close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma the empty sequence code close parenthesis and E open parenthesis M comma the empty sequence code close parenthesis
Read as: sigma is in capital sigma
Means: Notation for a machine prime s state set, tape alphabet, or defining tuple. Read as: sigma is in capital sigma
Read as: J
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: J
Read as: h open parenthesis e comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: h open parenthesis e comma w close parenthesis
Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x prime comma y close parenthesis and object language symbol S sub sigma open parenthesis x prime comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x prime comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis close parenthesis close parenthesis and next row then for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis the numeral for zero comma y close parenthesis and object language symbol S sub sigma open parenthesis the numeral for zero comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis the numeral for zero comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis the numeral for zero comma y prime close parenthesis and formula A open parenthesis the numeral for zero comma y close parenthesis and formula B open parenthesis y prime close parenthesis close parenthesis close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x prime comma y close parenthesis and object language symbol S sub sigma open parenthesis x prime comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x prime comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis close parenthesis close parenthesis and next row then for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis the numeral for zero comma y close parenthesis and object language symbol S sub sigma open parenthesis the numeral for zero comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis the numeral for zero comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis the numeral for zero comma y prime close parenthesis and formula A open parenthesis the numeral for zero comma y close parenthesis and formula B open parenthesis y prime close parenthesis close parenthesis close parenthesis
Read as: T prime open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T prime open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Read as: for every x, open parenthesis the numeral for k is less than x implies object language symbol S sub blank symbol open parenthesis x comma the numeral for zero close parenthesis close parenthesis
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: for every x, open parenthesis the numeral for k is less than x implies object language symbol S sub blank symbol open parenthesis x comma the numeral for zero close parenthesis close parenthesis
Read as: structure M prime satisfies T prime open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M prime satisfies T prime open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Read as: structure M satisfies E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M satisfies E open parenthesis M comma w close parenthesis
Read as: s sub M is in open parenthesis positive integers close parenthesis superscript
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: s sub M is in open parenthesis positive integers close parenthesis superscript
Read as: e is not equal to n
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: e is not equal to n
Read as: M prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: M prime
Read as: e equals n
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: e equals n
Read as: the tuple e comma n
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the tuple e comma n
Read as: f open parenthesis e comma n close parenthesis
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: f open parenthesis e comma n close parenthesis
Read as: the natural numbers
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: the natural numbers
Read as: structure M satisfies the numeral for k is not equal to the numeral for n
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M satisfies the numeral for k is not equal to the numeral for n
Read as: the interpretation of object language symbol S sub left end marker in structure M prime prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the interpretation of object language symbol S sub left end marker in structure M prime prime
Read as: object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis and object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for n close parenthesis semantically entails the disjunction over sub the tuple q comma sigma is in X open parenthesis object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis and object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for n close parenthesis close parenthesis
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis and object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for n close parenthesis semantically entails the disjunction over sub the tuple q comma sigma is in X open parenthesis object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis and object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for n close parenthesis close parenthesis
Read as: T open parenthesis M comma w close parenthesis semantically entails C open parenthesis M comma w comma n plus one close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis semantically entails C open parenthesis M comma w comma n plus one close parenthesis
Read as: Interpretation of the run structure. Predicate Q sub q contains exactly the pairs m and n for which machine M, started on input w, is in state q scanning square m after n steps. Predicate S sub sigma contains exactly the pairs m and n for which square m contains symbol sigma after n steps
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: Interpretation of the run structure. Predicate Q sub q contains exactly the pairs m and n for which machine M, started on input w, is in state q scanning square m after n steps. Predicate S sub sigma contains exactly the pairs m and n for which square m contains symbol sigma after n steps
Read as: m is less than i
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: m is less than i
Read as: the numeral for n
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the numeral for n
Read as: C open parenthesis M comma w comma k close parenthesis semantically entails E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: C open parenthesis M comma w comma k close parenthesis semantically entails E open parenthesis M comma w close parenthesis
Read as: C open parenthesis M comma w comma n close parenthesis semantically entails E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: C open parenthesis M comma w comma n close parenthesis semantically entails E open parenthesis M comma w close parenthesis
Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis and formula B open parenthesis y prime close parenthesis close parenthesis close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis and formula B open parenthesis y prime close parenthesis close parenthesis close parenthesis
Read as: structure M prime prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M prime prime
Read as: T prime open parenthesis M comma w close parenthesis semantically entails the numeral for k is less than the numeral for n
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: T prime open parenthesis M comma w close parenthesis semantically entails the numeral for k is less than the numeral for n
Read as: formula A
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: formula A
Read as: k
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: k
Read as: k minus m
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: k minus m
Read as: M equals the tuple Q comma capital sigma comma q sub zero comma delta
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: M equals the tuple Q comma capital sigma comma q sub zero comma delta
Read as: T open parenthesis M comma w close parenthesis semantically entails C open parenthesis M comma w comma n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis semantically entails C open parenthesis M comma w comma n close parenthesis
Read as: object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis and object language symbol S sub sigma sub zero open parenthesis the numeral for zero comma the numeral for n close parenthesis and and so on and object language symbol S sub sigma sub k open parenthesis the numeral for k comma the numeral for n close parenthesis and for every x, open parenthesis the numeral for k is less than x implies object language symbol S sub blank symbol open parenthesis x comma the numeral for n close parenthesis close parenthesis
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis and object language symbol S sub sigma sub zero open parenthesis the numeral for zero comma the numeral for n close parenthesis and and so on and object language symbol S sub sigma sub k open parenthesis the numeral for k comma the numeral for n close parenthesis and for every x, open parenthesis the numeral for k is less than x implies object language symbol S sub blank symbol open parenthesis x comma the numeral for n close parenthesis close parenthesis
Read as: object language symbol S sub sigma
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol S sub sigma
Read as: delta open parenthesis q sub zero comma blank symbol close parenthesis equals the tuple q sub zero comma blank symbol comma stay put
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q sub zero comma blank symbol close parenthesis equals the tuple q sub zero comma blank symbol comma stay put
Read as: the numeral for l prime is syntactically identical to the numeral for l plus one is syntactically identical to the numeral for m
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the numeral for l prime is syntactically identical to the numeral for l plus one is syntactically identical to the numeral for m
Read as: S
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: S
Read as: q
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: q
Read as: n equals maximum open parenthesis k comma the length of w close parenthesis
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: n equals maximum open parenthesis k comma the length of w close parenthesis
Read as: open parenthesis positive integers close parenthesis superscript
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: open parenthesis positive integers close parenthesis superscript
Read as: T open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis
Read as: delta open parenthesis q comma sigma close parenthesis equals the tuple q prime comma sigma prime comma move left
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q comma sigma close parenthesis equals the tuple q prime comma sigma prime comma move left
Read as: Left move induction display. For a positive head position m, let l be m minus one and instantiate the left move transition. The next configuration has state q prime scanning square l, writes sigma prime at square m, preserves every other listed square, and keeps the blank tail. At the leftmost square, use the boundary branch with current state q and successor state q prime, update square zero, and keep the head at square zero
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: Left move induction display. For a positive head position m, let l be m minus one and instantiate the left move transition. The next configuration has state q prime scanning square l, writes sigma prime at square m, preserves every other listed square, and keeps the blank tail. At the leftmost square, use the boundary branch with current state q and successor state q prime, update square zero, and keep the head at square zero
Read as: structure M prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M prime
Read as: T open parenthesis M comma w close parenthesis semantically entails C open parenthesis M comma w comma k close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis semantically entails C open parenthesis M comma w comma k close parenthesis
Read as: T prime open parenthesis M comma w close parenthesis semantically entails formula B open parenthesis the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T prime open parenthesis M comma w close parenthesis semantically entails formula B open parenthesis the numeral for n close parenthesis
Read as: State diagram. Purpose: Shows the same Even-machine behavior after replacing every state and symbol by a positive-integer code. Initial state: state one. States: state one, state two. Transition one: from state one, when reading three, write three, move right, and enter state two. Transition two: from state two, when reading two, write two, move right, and enter state two. Transition three: from state two, when reading three, write three, move right, and enter state one. Every displayed state has at least one outgoing transition
Means: A complete source-order transition linearization of the displayed state diagram. Read as: State diagram. Purpose: Shows the same Even-machine behavior after replacing every state and symbol by a positive-integer code. Initial state: state one. States: state one, state two. Transition one: from state one, when reading three, write three, move right, and enter state two. Transition two: from state two, when reading two, write two, move right, and enter state two. Transition three: from state two, when reading three, write three, move right, and enter state one. Every displayed state has at least one outgoing transition
Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x prime comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis close parenthesis close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x prime comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis close parenthesis close parenthesis
Read as: C open parenthesis M comma w comma n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: C open parenthesis M comma w comma n close parenthesis
Read as: object language symbol Q sub q
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol Q sub q
Read as: the numeral for one
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the numeral for one
Read as: sigma
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: sigma
Read as: C open parenthesis M comma w comma n plus one close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: C open parenthesis M comma w comma n plus one close parenthesis
Read as: the function isprime open parenthesis n close parenthesis equals cases begin; row one: one, if n is prime; row two: zero, otherwise; cases end
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: the function isprime open parenthesis n close parenthesis equals cases begin; row one: one, if n is prime; row two: zero, otherwise; cases end
Read as: m is in the natural numbers
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: m is in the natural numbers
Read as: C open parenthesis M comma w comma k close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: C open parenthesis M comma w comma k close parenthesis
Read as: y
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: y
Read as: U
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: U
Read as: E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: E open parenthesis M comma w close parenthesis
Read as: blank symbol
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: blank symbol
Read as: C open parenthesis M comma w comma zero close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: C open parenthesis M comma w comma zero close parenthesis
Read as: left end marker
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: left end marker
Read as: M sub e
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: M sub e
Read as: sigma sub i sub one
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: sigma sub i sub one
Read as: sigma is in capital sigma
Means: Notation for a machine prime s state set, tape alphabet, or defining tuple. Read as: sigma is in capital sigma
Read as: T open parenthesis M comma the empty sequence code close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma the empty sequence code close parenthesis
Read as: m equals k
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: m equals k
Read as: the set of integers from zero through n
Means: An explicit finite-set expression or equation that preserves the source braces as set enclosure. Read as: the set of integers from zero through n.
Read as: Q Cartesian product capital sigma Cartesian product the set containing move left, move right, and stay put
Means: An explicit finite-set expression or equation that preserves the source braces as set enclosure. Read as: Q Cartesian product capital sigma Cartesian product the set containing move left, move right, and stay put.
Read as: E
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: E
Read as: for every x, for every y, for every z, open parenthesis open parenthesis x is less than y and y is less than z close parenthesis implies x is less than z close parenthesis
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: for every x, for every y, for every z, open parenthesis open parenthesis x is less than y and y is less than z close parenthesis implies x is less than z close parenthesis
Read as: h
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: h
Read as: the tuple q comma sigma comma q prime comma sigma prime comma d
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the tuple q comma sigma comma q prime comma sigma prime comma d
Read as: the domain of structure M equals the natural numbers
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: the domain of structure M equals the natural numbers
Read as: object language symbol Q sub q sub zero open parenthesis the numeral for one comma the numeral for zero close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol Q sub q sub zero open parenthesis the numeral for one comma the numeral for zero close parenthesis
Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x prime comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis and formula B open parenthesis y prime close parenthesis close parenthesis close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x prime comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis and formula B open parenthesis y prime close parenthesis close parenthesis close parenthesis
Read as: T prime open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T prime open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Read as: formula B open parenthesis y close parenthesis is syntactically identical to for every x, open parenthesis x is less than y implies x is not equal to y close parenthesis
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: formula B open parenthesis y close parenthesis is syntactically identical to for every x, open parenthesis x is less than y implies x is not equal to y close parenthesis
Read as: object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis
Read as: structure M prime satisfies E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M prime satisfies E open parenthesis M comma w close parenthesis
Read as: n is in the domain of structure M equals the natural numbers
Means: A function type, value, or arithmetic relationship in the machine-computation convention. Read as: n is in the domain of structure M equals the natural numbers
Read as: delta open parenthesis q comma sigma close parenthesis
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q comma sigma close parenthesis
Read as: T open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis
Read as: the numeral for zero
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the numeral for zero
Read as: the domain of structure M prime equals the set of integers from zero through n; next row, the interpretation of the successor symbol in structure M prime at x equals x plus one if x is less than n, and equals n otherwise; next row, the tuple x comma y belongs to the interpretation of the less-than relation in structure M prime if and only if x is less than y or x equals y equals n
Means: An explicit finite-set expression or equation that preserves the source braces as set enclosure. Read as: the domain of structure M prime equals the set of integers from zero through n; next row, the interpretation of the successor symbol in structure M prime at x equals x plus one if x is less than n, and equals n otherwise; next row, the tuple x comma y belongs to the interpretation of the less-than relation in structure M prime if and only if x is less than y or x equals y equals n.
Read as: delta open parenthesis q comma sigma close parenthesis equals the tuple q prime comma sigma prime comma move right
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q comma sigma close parenthesis equals the tuple q prime comma sigma prime comma move right
Read as: the tuple q comma sigma
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the tuple q comma sigma
Read as: sigma prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: sigma prime
Read as: formula A open parenthesis the numeral for m comma the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: formula A open parenthesis the numeral for m comma the numeral for n close parenthesis
Read as: q sub zero
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: q sub zero
Read as: T open parenthesis M comma w close parenthesis semantically entails the numeral for m is less than the numeral for k
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: T open parenthesis M comma w close parenthesis semantically entails the numeral for m is less than the numeral for k
Read as: T prime open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T prime open parenthesis M comma w close parenthesis
Read as: delta open parenthesis q sub i comma sigma close parenthesis equals the tuple q sub j comma sigma prime comma move left
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q sub i comma sigma close parenthesis equals the tuple q sub j comma sigma prime comma move left
Read as: structure M satisfies there exists x, there exists y, open parenthesis the disjunction over sub the tuple q comma sigma is in X open parenthesis object language symbol Q sub q open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis close parenthesis
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: structure M satisfies there exists x, there exists y, open parenthesis the disjunction over sub the tuple q comma sigma is in X open parenthesis object language symbol Q sub q open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis close parenthesis
Read as: structure M satisfies T open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M satisfies T open parenthesis M comma w close parenthesis
Read as: the tuple q comma sigma
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the tuple q comma sigma
Read as: zero is less than or equal to n
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: zero is less than or equal to n
Read as: proves formula B
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: proves formula B
Read as: delta open parenthesis q sub i comma sigma close parenthesis equals the tuple q sub j comma sigma prime comma move right
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q sub i comma sigma close parenthesis equals the tuple q sub j comma sigma prime comma move right
Read as: q is in Q
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: q is in Q
Read as: structure M satisfies object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis and object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M satisfies object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis and object language symbol S sub sigma open parenthesis the numeral for m comma the numeral for n close parenthesis
Read as: formula A open parenthesis x comma y close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: formula A open parenthesis x comma y close parenthesis
Read as: structure M prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M prime
Read as: sigma sub zero
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: sigma sub zero
Read as: implies
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: implies
Read as: formula B
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: formula B
Read as: delta
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta
Read as: T prime open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T prime open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Read as: x is less than y
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: x is less than y
Read as: the domain of structure M prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: the domain of structure M prime
Read as: two
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: two
Read as: delta open parenthesis q comma sigma close parenthesis equals the tuple q prime comma sigma prime comma stay put
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q comma sigma close parenthesis equals the tuple q prime comma sigma prime comma stay put
Read as: capital sigma
Means: Notation for a machine prime s state set, tape alphabet, or defining tuple. Read as: capital sigma
Read as: capital sigma equals the set containing the left end marker, the blank symbol, and the stroke symbol
Means: An explicit finite-set expression or equation that preserves the source braces as set enclosure. Read as: capital sigma equals the set containing the left end marker, the blank symbol, and the stroke symbol.
Read as: the set containing zero and one
Means: An explicit finite-set expression or equation that preserves the source braces as set enclosure. Read as: the set containing zero and one.
Read as: two comma underbraced group one comma two sub Q comma three comma overbraced group one comma two comma three superscript capital sigma comma one comma underbraced group one comma three comma two comma three comma two sub delta open parenthesis one comma three close parenthesis equals the tuple two comma three comma move right comma overbraced group two comma two comma two comma two comma two superscript delta open parenthesis two comma two close parenthesis equals the tuple two comma two comma move right comma underbraced group two comma three comma one comma three comma two sub delta open parenthesis two comma three close parenthesis equals the tuple one comma three comma move right
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: two comma underbraced group one comma two sub Q comma three comma overbraced group one comma two comma three superscript capital sigma comma one comma underbraced group one comma three comma two comma three comma two sub delta open parenthesis one comma three close parenthesis equals the tuple two comma three comma move right comma overbraced group two comma two comma two comma two comma two superscript delta open parenthesis two comma two close parenthesis equals the tuple two comma two comma move right comma underbraced group two comma three comma one comma three comma two sub delta open parenthesis two comma three close parenthesis equals the tuple one comma three comma move right
Read as: is less than
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: is less than
Read as: s open parenthesis e close parenthesis equals cases begin; row one: zero, if machine M sub e does not halt for input e; row two: one, if machine M sub e halts for input e; cases end
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: s open parenthesis e close parenthesis equals cases begin; row one: zero, if machine M sub e does not halt for input e; row two: one, if machine M sub e halts for input e; cases end
Read as: sigma sub i sub k
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: sigma sub i sub k
Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis close parenthesis close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: for every x, for every y, open parenthesis open parenthesis object language symbol Q sub q sub i open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis implies next row then open parenthesis object language symbol Q sub q sub j open parenthesis x comma y prime close parenthesis and object language symbol S sub sigma prime open parenthesis x comma y prime close parenthesis and formula A open parenthesis x comma y close parenthesis close parenthesis close parenthesis
Read as: i
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: i
Read as: object language symbol S sub blank symbol open parenthesis the numeral for k prime comma the numeral for n prime close parenthesis
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: object language symbol S sub blank symbol open parenthesis the numeral for k prime comma the numeral for n prime close parenthesis
Read as: M sub one
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: M sub one
Read as: formula B
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: formula B
Read as: not formula B
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: not formula B
Read as: M
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: M
Read as: object language symbol zero prime prime
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol zero prime prime
Read as: delta open parenthesis q sub zero comma left end marker close parenthesis
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q sub zero comma left end marker close parenthesis
Read as: object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: object language symbol Q sub q open parenthesis the numeral for m comma the numeral for n close parenthesis
Read as: delta open parenthesis q comma sigma close parenthesis equals the tuple q prime comma sigma prime comma D
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q comma sigma close parenthesis equals the tuple q prime comma sigma prime comma D
Read as: M sub two
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: M sub two
Read as: the numeral for k is less than the numeral for k prime implies object language symbol S sub blank symbol open parenthesis the numeral for k prime comma the numeral for n prime close parenthesis
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: the numeral for k is less than the numeral for k prime implies object language symbol S sub blank symbol open parenthesis the numeral for k prime comma the numeral for n prime close parenthesis
Read as: the tuple q comma sigma is in X
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: the tuple q comma sigma is in X
Read as: q sub j
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: q sub j
Read as: the interpretation of successor symbol in structure M prime prime open parenthesis zero close parenthesis equals the interpretation of successor symbol in structure M prime prime open parenthesis one close parenthesis equals one
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: the interpretation of successor symbol in structure M prime prime open parenthesis zero close parenthesis equals the interpretation of successor symbol in structure M prime prime open parenthesis one close parenthesis equals one
Read as: five
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: five
Read as: semantically entails formula B
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: semantically entails formula B
Read as: language move left sub M
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: language move left sub M
Read as: T open parenthesis M comma w close parenthesis semantically entails E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis semantically entails E open parenthesis M comma w close parenthesis
Read as: structure M prime satisfies T prime open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: structure M prime satisfies T prime open parenthesis M comma w close parenthesis and E open parenthesis M comma w close parenthesis
Read as: T open parenthesis M comma w close parenthesis implies E open parenthesis M comma w close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: T open parenthesis M comma w close parenthesis implies E open parenthesis M comma w close parenthesis
Read as: the set containing q sub zero and q sub one
Means: An explicit finite-set expression or equation that preserves the source braces as set enclosure. Read as: the set containing q sub zero and q sub one.
Read as: delta open parenthesis q sub zero comma blank symbol close parenthesis equals the tuple q sub zero comma blank symbol comma stay put
Means: Transition notation specifying a current state and symbol or the resulting state, written symbol, and head movement. Read as: delta open parenthesis q sub zero comma blank symbol close parenthesis equals the tuple q sub zero comma blank symbol comma stay put
Read as: F
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: F
Read as: object language symbol Q sub q sub zero open parenthesis the numeral for one comma the numeral for n close parenthesis and object language symbol S sub left end marker open parenthesis the numeral for zero comma the numeral for n close parenthesis and for every x, open parenthesis the numeral for zero is less than x implies object language symbol S sub blank symbol open parenthesis x comma the numeral for n close parenthesis close parenthesis quad for all n is in the natural numbers next row then there exists y, open parenthesis object language symbol Q sub q sub zero open parenthesis the numeral for zero comma y close parenthesis and object language symbol S sub left end marker open parenthesis the numeral for zero comma y close parenthesis close parenthesis
Means: Notation for tape symbols, concatenated strings, or unary blocks. Read as: object language symbol Q sub q sub zero open parenthesis the numeral for one comma the numeral for n close parenthesis and object language symbol S sub left end marker open parenthesis the numeral for zero comma the numeral for n close parenthesis and for every x, open parenthesis the numeral for zero is less than x implies object language symbol S sub blank symbol open parenthesis x comma the numeral for n close parenthesis close parenthesis quad for all n is in the natural numbers next row then there exists y, open parenthesis object language symbol Q sub q sub zero open parenthesis the numeral for zero comma y close parenthesis and object language symbol S sub left end marker open parenthesis the numeral for zero comma y close parenthesis close parenthesis
Read as: there exists x, there exists y, open parenthesis the disjunction over sub the tuple q comma sigma is in X open parenthesis object language symbol Q sub q open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis close parenthesis
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: there exists x, there exists y, open parenthesis the disjunction over sub the tuple q comma sigma is in X open parenthesis object language symbol Q sub q open parenthesis x comma y close parenthesis and object language symbol S sub sigma open parenthesis x comma y close parenthesis close parenthesis close parenthesis
Read as: s open parenthesis e close parenthesis equals one
Means: An equation, comparison, or membership claim fixed by the surrounding source sentence. Read as: s open parenthesis e close parenthesis equals one
Read as: move left
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: move left
Read as: M sub three
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: M sub three
Read as: formula A open parenthesis the numeral for m comma the numeral for n close parenthesis
Means: A Turing-machine variable or term whose role is fixed by its exact source context. Read as: formula A open parenthesis the numeral for m comma the numeral for n close parenthesis
Figure containing two behaviorally equivalent Even-machine diagrams with renamed states and tape symbols.
First Even-machine variant, using states q zero and q one with stroke and blank tape symbols. State diagram. Purpose: Shows the Even-machine transition pattern before renaming, with initial state q zero and state q one. Initial state: state q sub zero. States: state q sub zero, state q sub one. Transition one: from state q sub zero, when reading stroke symbol, write stroke symbol, move right, and enter state q sub one. Transition two: from state q sub one, when reading blank symbol, write blank symbol, move right, and enter state q sub one. Transition three: from state q sub one, when reading stroke symbol, write stroke symbol, move right, and enter state q sub zero. Every displayed state has at least one outgoing transition
Second Even-machine variant, using states s and h and capital A in place of the stroke symbol. State diagram. Purpose: Shows the same transition pattern after renaming the states and stroke symbol. Initial state: state s. States: state s, state h. Transition one: from state s, when reading capital A symbol, write capital A symbol, move right, and enter state h. Transition two: from state h, when reading blank symbol, write blank symbol, move right, and enter state h. Transition three: from state h, when reading capital A symbol, write capital A symbol, move right, and enter state s. Every displayed state has at least one outgoing transition
Figure containing the standardized positive-integer encoding of the Even machine.
Standard Even-machine diagram with states one and two and encoded tape symbols two and three. State diagram. Purpose: Shows the same Even-machine behavior after replacing every state and symbol by a positive-integer code. Initial state: state one. States: state one, state two. Transition one: from state one, when reading three, write three, move right, and enter state two. Transition two: from state two, when reading two, write two, move right, and enter state two. Transition three: from state two, when reading three, write three, move right, and enter state one. Every displayed state has at least one outgoing transition
States that some functions from the natural numbers to the natural numbers are not Turing computable.
Unsolved exercise asking for a different finite description convention for standard machines and a simulation justification. The exercise is preserved as a task and intentionally remains unsolved.
Defines an index of a Turing machine in the fixed enumeration and introduces M sub e.
States the universal-machine simulation theorem and the associated partial function of a machine index and input.
Defines the total halting function h on a machine index and input.
Defines the Halting Problem as deciding whether indexed machine M sub e halts on unary input n.
Defines the diagonal halting function s by running indexed machine M sub e on its own index.
States that the diagonal halting function s is not Turing computable.
States the unsolvability of the Halting Problem and noncomputability of h.
Unsolved exercise asking for a proof that deciding halting on the fixed unary input three is impossible. The exercise is preserved as a task and intentionally remains unsolved.
Unsolved exercise asking to reduce diagonal cases to off-diagonal halting cases. The exercise is preserved as a task and intentionally remains unsolved.
Unsolved exercise asking whether taking machine descriptions rather than indices changes halting undecidability. The exercise is preserved as a task and intentionally remains unsolved.
Unsolved exercise asking why the partial self-halting indicator is Turing computable. The exercise is preserved as a task and intentionally remains unsolved.
Recursive definition of the numeral for zero and the successor numeral for n plus one.
Defines the first-order language L sub M used to represent states, tape symbols, numerals, successor, and order.
Universal transition sentence for a machine instruction that moves the head right.
Two-part universal transition sentence for a left move, including the left-end boundary case.
Universal transition sentence for an instruction that leaves the head in place.
States that the representation sentences entail numeral m is below numeral k whenever m is below k.
Unsolved exercise asking for a proof of the numeral-order proposition by induction. The exercise is preserved as a task and intentionally remains unsolved.
Defines sentence C of M, w, and n describing the complete machine configuration after n steps.
States that a represented halting configuration entails sentence E expressing eventual halting.
States that T of M and w entails the correct configuration sentence at every nonhalting stage.
Inductive right-move case deriving the next represented configuration from the current one.
Inductive left-move case, including the special behavior at the leftmost tape square.
Unsolved exercise asking to complete the stay-put case of the configuration induction. The exercise is preserved as a task and intentionally remains unsolved.
Unsolved exercise asking for a derivation that unchanged non-scanned squares retain their tape symbols. The exercise is preserved as a task and intentionally remains unsolved.
Unsolved exercise asking for a derivation of the shifted blank-tail condition. The exercise is preserved as a task and intentionally remains unsolved.
States that if M halts on w, the implication from T of M and w to E of M and w is valid.
States the converse: validity of the representing implication entails that M halts on w.
Defines the state and tape-symbol predicate interpretations in the structure built from an actual run.
States that no Turing machine decides validity of every first-order sentence.
States that satisfiability of arbitrary first-order sentences is undecidable.
States that first-order validity is semidecidable by enumerating derivations.
Unsolved exercise asking for a finite structure that makes the looping-machine representation and halting sentence true. The exercise is preserved as a task and intentionally remains unsolved.
Two conditions the finite countermodel exercise asks the reader to make true.
Modified right-move transition sentence with the freshness condition B of y prime.
Modified left-move transition sentence with ordinary and left-boundary branches.
Modified stay-put transition sentence with the freshness condition B of y prime.
States that a halting computation yields a finite model of T prime conjoined with E.
Defines the finite run structure domain, capped successor, and modified order relation.
Unsolved exercise asking to verify the finite model in the forward Trakhtenbrot lemma. The exercise is preserved as a task and intentionally remains unsolved.
States that a finite model of T prime conjoined with E entails the represented machine halts.
Unsolved exercise asking to derive the freshness sentence B at each nonhalting step. The exercise is preserved as a task and intentionally remains unsolved.
States Trakhtenbrot's theorem: finite satisfiability of first-order sentences is undecidable.
States that no derivation system is both sound and complete for validity over finite structures.
Unsolved exercise asking for the corollary from semidecidability and the finite-satisfiability reduction. The exercise is preserved as a task and intentionally remains unsolved.
link to exercise on enumerating finite sequences of positive integers
link to exercise showing functions from natural numbers to natural numbers are nonenumerable
link to the universal-machine simulation step that finds a matching instruction
link to proposition that represented numerals preserve strict order
link to definition of the first-order machine-description language
link to proposition that represented numerals preserve strict order
link to definition of the first-order machine-description language
link to lemma that a halting configuration entails the halting sentence
link to lemma that validity of the representation implies halting
link to lemma that halting implies validity of the representation
link to lemma that halting implies validity of the representation
link to lemma that validity of the representation implies halting
link to corollary that first-order satisfiability is undecidable
link to lemma that validity of the representation implies halting
link to lemma that validity of the representation implies halting
link to lemma that validity of the representation implies halting
link to proposition that represented numerals preserve strict order
link to corollary excluding a sound and complete proof system for finite validity