Cycles in triangle-free graphs of large chromatic number
نویسندگان
چکیده
منابع مشابه
Cycles in triangle-free graphs of large chromatic number
More than twenty years ago Erdős conjectured [4] that a triangle-free graph G of chromatic number k ≥ k0(ε) contains cycles of at least k2−ε different lengths as k →∞. In this paper, we prove the stronger fact that every triangle-free graph G of chromatic number k ≥ k0(ε) contains cycles of 1 64 (1− ε)k 2 log k4 consecutive lengths, and a cycle of length at least 14 (1− ε)k 2 log k. As there ex...
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ژورنال
عنوان ژورنال: Combinatorica
سال: 2016
ISSN: 0209-9683,1439-6912
DOI: 10.1007/s00493-015-3262-0