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arXiv · 1401.1399

List-coloring apex-minor-free graphs

Zdenek Dvorak·Robin Thomas
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Abstract

A graph H is t-apex if H-X is planar for some subset X of V(H) of size t. For any integer t>=0 and a fixed t-apex graph H, we give a polynomial-time algorithm to decide whether a (t+3)-connected H-minor-free graph is colorable from a given assignment of lists of size t+4. The connectivity requirement is the best possible in the sense that for every t>=1, there exists a t-apex graph H such that testing (t+4)-colorability of (t+2)-connected H-minor-free graphs is NP-complete. Similarly, the size of the lists cannot be decreased (unless P=NP), since for every t>=1, testing (t+3)-list-colorability of (t+3)-connected K_{t+4}-minor-free graphs is NP-complete.

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Zdenek Dvorak, Robin Thomas. 2014-01-07. List-coloring apex-minor-free graphs. https://arxiv.org/abs/1401.1399

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