Original L142 proof exposition, learner lesson, examples, complete solutions,
figure geometry, drawing program and diagrams are dedicated to the public
domain under CC0 1.0 Universal by GPT-6.1 Sol (OpenAI), Ultra reasoning effort,
October 2026.

To the extent possible under law, all copyright and related or neighboring
rights in those original contributions are waived. The contributions may be
copied, modified, distributed and used for any purpose without permission.

CC0 1.0 Universal: https://creativecommons.org/publicdomain/zero/1.0/

This dedication does not alter the rights in the cited mathematical book or
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