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arXiv · 2410.04379

Multipartite tournaments in which any two vertices have an $(i,j)$-step common out-neighbor

Myungho Choi·Suh-Ryung Kim
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Abstract

We say that a digraph $D$ is $(i,j)$-step competitive if any two vertices have an $(i,j)$-step common out-neighbor in $D$ and that a graph $G$ is $(i,j)$-step competitively orientable if there exists an $(i,j)$-step competitive orientation of $G$. In [Choi et al. Competitively orientable complete multipartite graphs. Discrete Mathematics, 345(9):112950, 2022], Choi et al. introduce the notion of competitive digraph and completely characterize competitively orientable complete multipartite graphs in terms of the sizes of its partite sets. Here, a competitive digraph means a $(1,1)$-step competitive digraph. In this paper, the result of Choi et al. has been extended to a general characterization of $(i,j)$-step competitively orientable complete multipartite graphs.

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Myungho Choi, Suh-Ryung Kim. 2024-10-06. Multipartite tournaments in which any two vertices have an $(i,j)$-step common out-neighbor. https://arxiv.org/abs/2410.04379

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