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arXiv · 2411.13483

Oriented Trees in Digraphs without Oriented $4$-cycles

Maya Stein·Ana Trujillo-Negrete
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Abstract

We prove that if $D$ is a digraph of maximum outdegree and indegree at least $k$, and minimum semidegree at least $k/2$ that contains no oriented $4$-cycles, then $D$ contains each oriented tree $T$ with~$k$ arcs. This can be slightly improved if $T$ is either antidirected or an arborescence.

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Maya Stein, Ana Trujillo-Negrete. 2024-11-20. Oriented Trees in Digraphs without Oriented $4$-cycles. https://arxiv.org/abs/2411.13483

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