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arXiv · 2208.05254

Continued Fractions and the 4-Color Theorem

Richard Evan Schwartz
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Abstract

We study the geometry of some proper 4-colorings of the vertices of sphere triangulations with degree sequence 6,...,6,2,2,2. Such triangulations are the simplest examples which have non-negative combinatorial curvature. The examples we construct, which are roughly extremal in some sense, are based on a novel geometric interpretation of continued fractions. We also present a conjectural sharp "isoperimetric inequality" for colorings of this kind of triangulation.

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Richard Evan Schwartz. 2026-01-09. Continued Fractions and the 4-Color Theorem. https://arxiv.org/abs/2208.05254

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