Disproving the normal graph conjecture
نویسندگان
چکیده
A graph G is called normal if there exist two coverings, C and S of its vertex set such that every member induces a clique in G, an independent C∩S≠∅ for C∈C S∈S. It has been conjectured by De Simone Körner 1999 does not contain C5, C7 C7‾ as induced subgraph. We disprove this conjecture.
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 2021
ISSN: ['0095-8956', '1096-0902']
DOI: https://doi.org/10.1016/j.jctb.2020.04.001