The Upper Clique Transversal Problem
Abstract
A clique transversal in a graph is a set of vertices intersecting all maximal cliques. The problem of determining the minimum size of a clique transversal has received considerable attention in the literature. In this paper, we initiate the study of the ''upper'' variant of this parameter, the upper clique transversal number, defined as the maximum size of a minimal clique transversal. We investigate this parameter from the algorithmic and complexity points of view, with a focus on various graph classes. We show that the corresponding decision problem is NP-complete in the classes of chordal graphs, chordal bipartite graphs, cubic planar bipartite graphs, and line graphs of bipartite graphs, but solvable in linear time in the classes of split graphs, proper interval graphs, and cographs, and in polynomial time for graphs of bounded cliquewidth. We conclude the paper with a number of open questions.
Keywords
Cite
@article{arxiv.2309.14103,
title = {The Upper Clique Transversal Problem},
author = {Martin Milanič and Yushi Uno},
journal= {arXiv preprint arXiv:2309.14103},
year = {2024}
}
Comments
A preliminary version appeared in the proceedings of the 49th International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2023)