Clique-Transversal Sets in Cubic Graphs

نویسندگان

Zuosong Liang

Erfang Shan

T. C. Edwin Cheng

چکیده

A clique-transversal set S of a graph G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted τc(G), is the minimum cardinality of a clique-transversal set in G. In this paper we present an upper bound and a lower bound on τc(G) for cubic graphs, and characterize the extremal cubic graphs achieving the lower bound. In addition, we present a sharp upper bound on τc(G) for claw-free cubic graphs.

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