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arXiv · 1705.07270

Conflict-free vertex-connections of graphs

Xueliang Li·Yingying Zhang·Xiaoyu Zhu·Yaping Mao·Haixing Zhao
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Abstract

A path in a vertex-colored graph is called \emph{conflict free} if there is a color used on exactly one of its vertices. A vertex-colored graph is said to be \emph{conflict-free vertex-connected} if any two vertices of the graph are connected by a conflict-free path. This paper investigates the question: For a connected graph $G$, what is the smallest number of colors needed in a vertex-coloring of $G$ in order to make $G$ conflict-free vertex-connected. As a result, we get that the answer is easy for $2$-connected graphs, and very difficult for connected graphs with more cut-vertices, including trees.

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Xueliang Li, Yingying Zhang, Xiaoyu Zhu, Yaping Mao, Haixing Zhao. 2017-05-20. Conflict-free vertex-connections of graphs. https://arxiv.org/abs/1705.07270

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