Ramsey-type results for unions of comparability graphs and convex sets inrestricted position
نویسندگان
چکیده
A graph on n vertices which is the union of two comparability graphs on the same vertex set, always contains a clique or independent set of size n 1 3 . On the other hand, there exist such graphs for which the largest clique and independent set are of size at most n. Similar results are obtained for graphs which are a union of a fixed number k of comparability graphs. We also show that the same bounds hold for unions of perfect graphs. A geometric application is included.
منابع مشابه
Ramsey-Type Results for Unions of Comparability Graphs
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