Union-closed families of sets
نویسندگان
چکیده
A family of sets is union-closed if it contains the union of any two of its elements. Some years ago, Reimer gave a lower bound for the average size of an element of a union-closed family consisting of m sets and, two years ago, Czédli did the same under the additional condition that our sets are contained in a set with n elements. Recently Tom Eccles and I have determined the minimum average size precisely, and so proved a conjecture of Czédli, Maróti and Schmidt. In the talk I shall prove this result, and shall present some of its consequences.
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 120 شماره
صفحات -
تاریخ انتشار 2013