Intersecting Families of Finite Sets and Fixed-point-Free 2-Elements
نویسندگان
چکیده
We study the maximum cardinality of a pairwise-intersecting family of subsets of an n-set, or the size of the smallest set in such a family, under either of the assumptions that it is regular (as a hypergraph) or that it admits a transitive permutation group. Not surprisingly, results under the second assumption are stronger. We also give some results for 4-wise intersecting families under the same assumptions.
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 10 شماره
صفحات -
تاریخ انتشار 1989