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arXiv · 1503.00965

Colorful paths for 3-chromatic graphs

Bessy Stéphane·Bousquet Nicolas
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Abstract

In this paper, we prove that every 3-chromatic connected graph, except $C_7$, admits a 3-vertex coloring in which every vertex is the beginning of a 3-chromatic path. It is a special case of a conjecture due to S.~Akbari, F.~Khaghanpoor, and S.~Moazzeni, cited in [P.J. Cameron, Research problems from the BCC22, \emph{Discrete Math.} {\bf 311} (2011), 1074--1083], stating that every connected graph $G$ other than $C_7$ admits a $\chi (G)$-coloring such that every vertex of $G$ is the beginning of a colorful path (i.e. a path of on $\chi(G)$ vertices containing a vertex of each color). We also provide some support for the conjecture in the case of 4-chromatic graphs.

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Bessy Stéphane, Bousquet Nicolas. 2015-03-03. Colorful paths for 3-chromatic graphs. https://arxiv.org/abs/1503.00965

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