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On the Size of Set Systems on [n] Not Containing Weak (r, Δ)-Systems

✍ Scribed by Vojtěch Rödl; Luboš Thoma


Publisher
Elsevier Science
Year
1997
Tongue
English
Weight
286 KB
Volume
80
Category
Article
ISSN
0097-3165

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✦ Synopsis


Let r 3 be an integer. A weak (r, 2)-system is a family of r sets such that all pairwise intersections among the members have the same cardinality. We show that for n large enough, there exists a family F of subsets of [n] such that F does not contain a weak (r, 2)-system and |F| 2 (1Â3) } n 1Â5 log 4Â5 (r&1) . This improves an earlier