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arXiv · 2203.09256

The bondage number of chordal graphs

Valentin Bouquet
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Abstract

A set $S\subseteq V(G)$ of a graph $G$ is a dominating set if each vertex has a neighbor in $S$ or belongs to $S$. Let $γ(G)$ be the cardinality of a minimum dominating set in $G$. The bondage number $b(G)$ of a graph $G$ is the smallest cardinality of a set edges $A\subseteq E(G)$ such that $γ(G-A)=γ(G)+1$. A chordal graph is a graph with no induced cycle of length four or more. In this paper, we prove that the bondage number of a chordal graph $G$ is at most the order of its maximum clique, that is, $b(G)\leq ω(G)$. We show that this bound is best possible.

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Valentin Bouquet. 2022-03-17. The bondage number of chordal graphs. https://arxiv.org/abs/2203.09256

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