Finite subgraphs of uncountably chromatic graphs
نویسندگان
چکیده
منابع مشابه
Finite subgraphs of uncountably chromatic graphs
It is consistent that for every function f : ω → ω there is a graph with size and chromatic number א1 in which every n-chromatic subgraph contains at least f(n) vertices (n ≥ 3). This solves a $ 250 problem of Erdős. It is consistent that there is a graph X with Chr(X) = |X| = א1 such that if Y is a graph all whose finite subgraphs occur in X then Chr(Y ) ≤ א2 (so the Taylor conjecture may fail...
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ژورنال
عنوان ژورنال: Journal of Graph Theory
سال: 2005
ISSN: 0364-9024,1097-0118
DOI: 10.1002/jgt.20060