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arXiv · 1708.08641

Vertex-disjoint properly edge-colored cycles in edge-colored complete graphs

Ruonan Li·Hajo Broersma·Shenggui Zhang
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Abstract

It is conjectured that every edge-colored complete graph $G$ on $n$ vertices satisfying $\Delta^{mon}(G)\leq n-3k+1$ contains $k$ vertex-disjoint properly edge-colored cycles. We confirm this conjecture for $k=2$, prove several additional weaker results for general $k$, and we establish structural properties of possible minimum counterexamples to the conjecture. We also reveal a close relationship between properly edge-colored cycles in edge-colored complete graphs and directed cycles in multi-partite tournaments. Using this relationship and our results on edge-colored complete graphs, we obtain several partial solutions to a conjecture on disjoint cycles in directed graphs due to Bermond and Thomassen.

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Ruonan Li, Hajo Broersma, Shenggui Zhang. 2017-08-29. Vertex-disjoint properly edge-colored cycles in edge-colored complete graphs. https://arxiv.org/abs/1708.08641

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