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arXiv · 1402.2135

Graph classes with and without powers of bounded clique-width

Flavia Bonomo·Luciano N. Grippo·Martin Milanič·Martín D. Safe
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Abstract

We initiate the study of graph classes of power-bounded clique-width, that is, graph classes for which there exist integers $k$ and $\ell$ such that the $k$-th powers of the graphs are of clique-width at most $\ell$. We give sufficient and necessary conditions for this property. As our main results, we characterize graph classes of power-bounded clique-width within classes defined by either one forbidden induced subgraph, or by two connected forbidden induced subgraphs. We also show that for every positive integer $k$, there exists a graph class such that the $k$-th powers of graphs in the class form a class of bounded clique-width, while this is not the case for any smaller power.

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Flavia Bonomo, Luciano N. Grippo, Martin Milanič, Martín D. Safe. 2014-02-10. Graph classes with and without powers of bounded clique-width. https://doi.org/10.1016/j.dam.2015.06.010

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