N ov 2 01 0 The Fractional Chromatic Number of Triangle - free Graphs with ∆ ≤ 3
نویسندگان
چکیده
Let G be any triangle-free graph with maximum degree ∆ ≤ 3. Staton proved that the independence number of G is at least 5 14 n. Heckman and Thomas conjectured that Staton’s result can be strengthened into a bound on the fractional chromatic number of G, namely χf (G) ≤ 14 5 . Recently, Hatami and Zhu proved χf (G) ≤ 3− 3 64 . In this paper, we prove χf (G) ≤ 3− 3 43 .
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