On transversals in minimal imperfect graphs

نویسندگان

  • Jean-Luc Fouquet
  • Frédéric Maire
  • Irena Rusu
  • Henri Thuillier
چکیده

V. Chv atal proved that no minimal imperfect graph has a small transversal, that is, a set of vertices of cardinality at most + ! 1 which meets every !-clique and every -stable set. In this paper we prove that a slight generalization of this notion of small transversal leads to a conjecture which is as strong as Berge's Strong Perfect Graph Conjecture for a very large class of graphs, although it seems to be weaker than Berge's conjecture for those graphs whose diameter does not exceed 6. 3

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عنوان ژورنال:
  • Discrete Mathematics

دوره 165-166  شماره 

صفحات  -

تاریخ انتشار 1997