Remarks on an Edge Isoperimetric Problem
نویسنده
چکیده
Among all collections of a given number of k-element subsets of an n-element groundset find a collection which maximizes the number of pairs of subsets which intersect in k − 1 elements. This problem was solved for k = 2 by Ahlswede and Katona, and is open for k > 2. We survey some linear algebra approaches which yield to estimations for the maximum number of pairs, and we present a new and short proof of the Ahlswede-Katona result.
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عنوان ژورنال:
- Electronic Notes in Discrete Mathematics
دوره 21 شماره
صفحات -
تاریخ انتشار 2005