1-perfectly orientable graphs and graph products
نویسندگان
چکیده
منابع مشابه
1-perfectly Orientable Graphs and Graph Products
A graph G is said to be 1-perfectly orientable (1-p.o. for short) if it admits an orientation such that the out-neighborhood of every vertex is a clique in G. The class of 1-p.o. graphs forms a common generalization of the classes of chordal and circular arc graphs. Even though 1-p.o. graphs can be recognized in polynomial time, no structural characterization of 1-p.o. graphs is known. In this ...
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We study the class of 1-perfectly orientable (1-p.o.) graphs, that is, graphs having an orientation in which every out-neighborhood induces a tournament. 1-p.o. graphs form a common generalization of chordal graphs and circular arc graphs. Even though 1-p.o. graphs can be recognized in polynomial time, little is known about their structure. In this paper, we prove several structural results abo...
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If G is a graph then a subgraph H is isometric if, for every pair of vertices u, v of H, we have dH(u, v) = dG(u, v) where d is the distance function. We say a graph G is distance preserving (dp) if it has an isometric subgraph of every possible order up to the order of G. We give a necessary and sufficient condition for the lexicographic product of two graphs to be a dp graph. A graph G is seq...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2017
ISSN: 0012-365X
DOI: 10.1016/j.disc.2016.09.023