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Induced trees in graphs of large chromatic number

✍ Scribed by Scott, A. D.

Publisher: John Wiley and Sons
Year: 1997
Tongue: English
Weight: 134 KB
Volume: 24
Category: Article
ISSN: 0364-9024
DOI: 10.1002/(sici)1097-0118(199704)24:4<297::aid-jgt2>3.0.co;2-j

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✦ Synopsis

Gyárfás and Sumner independently conjectured that for every tree T and integer k there is an integer f (k, T ) such that every graph G with χ(G) > f(k, t) contains either K k or an induced copy of T . We prove a `topological´version of the conjecture: for every tree T and integer k there is g(k, T ) such that every graph G with χ(G) > g(k, t) contains either K k or an induced copy of a subdivision of T .

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