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arXiv · 1307.4901

Oriented chromatic number of Halin graphs

Janusz Dybizbański·Andrzej Szepietowski
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Abstract

Oriented chromatic number of an oriented graph $G$ is the minimum order of an oriented graph $H$ such that $G$ admits a homomorphism to $H$. The oriented chromatic number of an unoriented graph $G$ is the maximal chromatic number over all possible orientations of $G$. In this paper, we prove that every Halin graph has oriented chromatic number at most 8, improving a previous bound by Hosseini Dolama and Sopena, and confirming the conjecture given by Vignal.

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Janusz Dybizbański, Andrzej Szepietowski. 2013-07-18. Oriented chromatic number of Halin graphs. https://doi.org/10.1016/j.ipl.2013.09.011

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