A combinatorial proof for the circular chromatic number of Kneser graphs
نویسندگان
چکیده
Chen [4] confirmed the Johnson-Holroyd-Stahl conjecture that the circular chromatic number of a Kneser graph is equal to its chromatic number. A shorter proof of this result was given by Chang, Liu, and Zhu [3]. Both proofs were based on Fan’s lemma [5] in algebraic topology. In this article we give a further simplified proof of this result. Moreover, by specializing a constructive proof of Fan’s lemma by Prescott and Su [19], our proof is self-contained and combinatorial.
منابع مشابه
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ورودعنوان ژورنال:
- J. Comb. Optim.
دوره 32 شماره
صفحات -
تاریخ انتشار 2016