EKR type inequalities for 4-wise intersecting families
نویسنده
چکیده
Let 1 ≤ t ≤ 7 be an integer and let F be a k-uniform hypergraph on n vertices. Suppose that |A∩B∩C∩D| ≥ t holds for all A,B,C,D ∈ F . Then we have |F | ≤ (n−t k−t ) if | k n − 2 |< ε holds for some ε > 0 and all n > n0(ε). We apply this result to get EKR type inequalities for “intersecting and union families” and “intersecting Sperner families.”
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عنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 114 شماره
صفحات -
تاریخ انتشار 2007