On the average size of sets in intersecting Sperner families

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On the average size of sets in intersecting Sperner families

We show that the average size of subsets of [n] forming an intersecting Sperner family of cardinality not less than ( n−1 k−1 ) is at least k provided that k 6 n=2− √ n=2 + 1. The statement is not true if n=2¿ k ¿n=2−√8n+ 1=8+9=8. c © 2002 Elsevier Science B.V. All rights reserved.

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ژورنال

عنوان ژورنال: Discrete Mathematics

سال: 2002

ISSN: 0012-365X

DOI: 10.1016/s0012-365x(02)00429-6