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arXiv · 1505.03962

Deciding 4-colorability of planar triangulations

Martin Loebl
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Abstract

We show, without using the Four Color Theorem, that for each planar triangulation, the number of its proper vertex colorings by 4 colors is a determinant and thus can be calculated in a polynomial time. In particular, we can efficiently decide if the number is non-zero.

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Martin Loebl. 2016-03-22. Deciding 4-colorability of planar triangulations. https://arxiv.org/abs/1505.03962

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