The Maximum Size of 3-Wise Intersecting and 3-Wise Union Families
نویسندگان
چکیده
Let F be an n-uniform hypergraph on 2n vertices. Suppose that |F1 ∩ F2 ∩ F3| ≥ 1 and |F1 ∪ F2 ∪ F3| ≤ 2n− 1 holds for all F1, F2, F3 ∈ F . We prove that the size of F is at most ( 2n−2 n−1 ) .
منابع مشابه
The maximum size of 4-wise 2-intersecting and 4-wise 2-union families
Let F be an n-uniform hypergraph on 2n vertices. Suppose that |F1∩F2∩F3∩F4| ≥ 2 and |F1∪F2∪F3∪ F4| ≤ n−2 holds for all F1,F2,F3,F4 ∈F . We prove that the size of F is at most (2n−4 n−2 ) for n sufficiently large.
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ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 22 شماره
صفحات -
تاریخ انتشار 2006