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Neighborhood perfect graphs

โœ Scribed by J Lehel; Zs Tuza


Publisher
Elsevier Science
Year
1986
Tongue
English
Weight
595 KB
Volume
61
Category
Article
ISSN
0012-365X

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โœฆ Synopsis


The notion of neighborhood perfect graphs is introduced here as follows. Let G be a graph, ~N(G) denote the maximum number of edges such that no two of them belong to the same subgraph of G induced by the (closed) neighborhood of some vertex; let PN(G) be the minimum number of vertices whose neighborhood subgraphs cover the edge set of G. Then G is called neighborhood perfect if PN(G') = CrN(G' ) holds for every induced subgraph G' of G. It is expected that neighborhood perfect graphs are perfect also in the sense of Berge. We characterize here those chordal graphs which are neighborhood perfect. In addition, an algorithm to compute PN(G) = ON(G) is given for interval graphs.


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