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arXiv · 2110.07133

On well-edge-dominated graphs

Sarah E. Anderson·Kirsti Kuenzel·Douglas F. Rall
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Abstract

A graph is said to be well-edge-dominated if all its minimal edge dominating sets are minimum. It is known that every well-edge-dominated graph $G$ is also equimatchable, meaning that every maximal matching in $G$ is maximum. In this paper, we show that if $G$ is a connected, triangle-free, nonbipartite, well-edge-dominated graph, then $G$ is one of three graphs. We also characterize the well-edge-dominated split graphs and Cartesian products. In particular, we show that a connected Cartesian product $G\Box H$ is well-edge-dominated, where $G$ and $H$ have order at least $2$, if and only if $G\Box H = K_2 \Box K_2$.

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Sarah E. Anderson, Kirsti Kuenzel, Douglas F. Rall. 2021-10-14. On well-edge-dominated graphs. https://arxiv.org/abs/2110.07133

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