Great intersecting families of edges in hereditary hypergraphs
نویسنده
چکیده
Chvfital stated in 1972 the following conjecture: If Y~ is a hereditary hypergraph on S and .gCcy~ is a family of maximum cardinality of pairwise intersecting members of ~, then there exists an xeS such that d~(x)=l{HeYe:xeH}l=l.al. Berge and Schrnheim proved that 1~1~½ I~el for every ~ and ~. Now we prove that if there exists an .~, I~1 = [½ I~el] then Chvfital's conjecture is true for this ~.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 48 شماره
صفحات -
تاریخ انتشار 1984