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arXiv · 2307.13964

Recognition of chordal graphs and cographs which are Cover-Incomparability graphs

Arun Anil·Manoj Changat
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Abstract

Cover-Incomparability graphs (C-I graphs) are an interesting class of graphs from posets. A C-I graph is a graph from a poset $P=(V,\le)$ with vertex set $V$, and the edge-set is the union of edge sets of the cover graph and the incomparability graph of the poset. The recognition of the C-I graphs is known to be NP-complete (Maxov\'{a} et al., Order 26(3), 229--236(2009)). In this paper, we prove that chordal graphs having at most two independent simplicial vertices are exactly the chordal graphs which are also C-I graphs. A similar result is obtained for cographs as well. Using the structural results of these graphs, we derive linear time recognition algorithms for chordal graphs and cographs which are C-I graphs.

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BibTeXRIS

Arun Anil, Manoj Changat. 2023-07-26. Recognition of chordal graphs and cographs which are Cover-Incomparability graphs. https://doi.org/10.46298/dmtcs.11657

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