Complexity of clique-coloring odd-hole-free graphs
✍ Scribed by David Défossez
- Publisher
- John Wiley and Sons
- Year
- 2009
- Tongue
- English
- Weight
- 155 KB
- Volume
- 62
- Category
- Article
- ISSN
- 0364-9024
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✦ Synopsis
Abstract
In this paper we investigate the problem of clique‐coloring, which consists in coloring the vertices of a graph in such a way that no monochromatic maximal clique appears, and we focus on odd‐hole‐free graphs. On the one hand we do not know any odd‐hole‐free graph that is not 3‐clique‐colorable, but on the other hand it is NP‐hard to decide if they are 2‐clique‐colorable, and we do not know if there exists any bound k~0~ such that they are all k~0~ ‐clique‐colorable. First we will prove that (odd hole, codiamond)‐free graphs are 2‐clique‐colorable. Then we will demonstrate that the complexity of 2‐clique‐coloring odd‐hole‐free graphs is actually Σ~2~ P‐complete. Finally we will study the complexity of deciding whether or not a graph and all its subgraphs are 2‐clique‐colorable. © 2009 Wiley Periodicals, Inc. J Graph Theory 62: 139–156, 2009
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