Induced subtrees in graphs of large chromatic number
نویسندگان
چکیده
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 Kk 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 Kk or an induced copy of a subdivision of T .
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عنوان ژورنال:
- Discrete Mathematics
دوره 30 شماره
صفحات -
تاریخ انتشار 1980