Claw-free Graphs VI. Colouring Claw-free Graphs

نویسندگان

  • Maria Chudnovsky
  • Paul Seymour
چکیده

In this paper we prove that if G is a connected claw-free graph with three pairwise non-adjacent vertices, with chromatic number χ and clique number ω, then χ ≤ 2ω and the same for the complement of G. We also prove that the choice number of G is at most 2ω, except possibly in the case when G can be obtained from a subgraph of the Schläfli graph by replicating vertices. Finally, we show that the constant 2 is best possible in all cases.

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تاریخ انتشار 2009