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arXiv · 2507.12737

The Total Coloring Conjecture holds for planar graphs without three special subgraphs

Rongjin Su·Gang Fang·Enqiang Zhu
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Abstract

The Total Coloring Conjecture (TCC) for planar graphs with a maximum degree of six remains open. Previous studies suggest that TCC is valid for such graphs if they do not contain any subgraph isomorphic to a 4-fan. In this paper, we present an improved conclusion by establishing that TCC holds for planar graphs that are free of three particular substructures, namely the mushroom, the tent, and the cone. This advancement enhances previous findings by demonstrating that TCC is applicable to planar graphs with a maximum degree of six, which can accommodate sparse 4-fans, 5-fans, 5-wheels, and 6-wheels.

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Rongjin Su, Gang Fang, Enqiang Zhu. 2025-07-17. The Total Coloring Conjecture holds for planar graphs without three special subgraphs. https://arxiv.org/abs/2507.12737

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