Cycle length parities and the chromatic number
نویسندگان
چکیده
منابع مشابه
Cycle length parities and the chromatic number
In 1966 Erdős and Hajnal proved that the chromatic number of graphs whose odd cycles have lengths at most l is at most l + 1. Similarly, in 1992 Gyárfás proved that the chromatic number of graphs which have at most k odd cycle lengths is at most 2k + 2 which was originally conjectured by Bollobás and Erdős. Here we consider the influence of the parities of the cycle lengths modulo some odd prim...
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ژورنال
عنوان ژورنال: Journal of Graph Theory
سال: 2009
ISSN: 0364-9024,1097-0118
DOI: 10.1002/jgt.20450