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On the density of sets of vectors

✍ Scribed by Noga Alon

Publisher
Elsevier Science
Year
1983
Tongue
English
Weight
143 KB
Volume
46
Category
Article
ISSN
0012-365X

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✦ Synopsis

Answering a question of Erd6s, Sauer [4] and indepe~dently Pcrles and Shelah [5] found the maximal cardinality of a collection ~ of subsets of a se~: N of cardinality n such that for ever/ subset M ~ N of cardinality m I{C f3 M: C ~ 3b'}l < 2". Karl~)vsky and Milman [3] generalised this result. Here we give a short proof of these results and further extensions.

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