Applications of hypergraph coloring to coloring graphs not inducing certain trees
โ Scribed by H.A. Kierstead; V. Rodl
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 385 KB
- Volume
- 150
- Category
- Article
- ISSN
- 0012-365X
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โฆ Synopsis
We present a simple result on coloring hypergraphs and use it to obtain bounds on the chromatic number of graphs which do not induce certain trees.
O. Introduction
A class of graphs F is said to be x-bounded if there exists a functionfsuch that for all graphs G e F, (.) z(G) <~f(og(G)), where ;t(G) is the chromatic number of G and t~(G) is the clique size of G. The class F is said to be weakly ;t-bounded if there exists a constant c such that ;t(G) <~ c, for every triangle-free graph G e F. Let G = (V, E) be a graph with X c V. Then G IX] denotes the graph induced by X in G, i.e.,
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