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arXiv · 2604.24183

Conflict-free chromatic index of bipartite graphs

Yuxin Jin·Yuping Gao
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Abstract

An edge coloring of a graph $G$ is called conflict-free if, for every edge, its closed neighborhood contains a color that appears exactly once. The least number of colors required for such a coloring is the conflict-free chromatic index of $G$, denoted by $χ'_{CF}(G)$. Kamyczura, Meszka, and Przybyło conjectured that $χ'_{CF}(G)\le 3$ for any bipartite graph $G$ without isolated vertices. In this paper, we confirm this conjecture.

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Yuxin Jin, Yuping Gao. 2026-04-27. Conflict-free chromatic index of bipartite graphs. https://arxiv.org/abs/2604.24183

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