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arXiv · 2203.16314

List $4$-colouring of planar graphs

Xuding Zhu
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Abstract

This paper proves the following result: If $G$ is a planar graph and $L$ is a $4$-list assignment of $G$ such that $|L(x) \cap L(y)| \le 2$ for every edge $xy$, then $G$ is $L$-colourable. This answers a question asked by Kratochvíl, Tuza and Voigt in [Journal of Graph Theory, 27(1):43--49, 1998].

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Xuding Zhu. 2022-05-24. List $4$-colouring of planar graphs. https://arxiv.org/abs/2203.16314

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