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arXiv · 1402.7368

Color identical pairs in 4-chromatic graphs

Asbjørn Brændeland
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Abstract

I argue that, given vertices u and v in a 4-chromatic graph G, if the color of u equals the color of v in every 4-coloring of G then G has no planar supergraph where u and v are adjacent. This is equivalent to the Four Color Theorem.

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Asbjørn Brændeland. 2014-02-28. Color identical pairs in 4-chromatic graphs. https://arxiv.org/abs/1402.7368

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