Improved Ramsey-type results for comparability graphs
نویسندگان
چکیده
منابع مشابه
Ramsey-Type Results for Unions of Comparability Graphs
It is well known that the comparability graph of any partially ordered set of n elements contains either a clique or an independent set of size at least pn. In this note we show that any graph of n vertices which is the union of two comparability graphs on the same vertex set, contains either a clique or an independent set of size at least n 13 . On the other hand, there exist such graphs for w...
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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...
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ژورنال
عنوان ژورنال: Combinatorics, Probability and Computing
سال: 2020
ISSN: 0963-5483,1469-2163
DOI: 10.1017/s0963548320000103