Maximum Antichains in Random Subsets of a Finite Set
β Scribed by Deryk Osthus
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 125 KB
- Volume
- 90
- Category
- Article
- ISSN
- 0097-3165
No coin nor oath required. For personal study only.
β¦ Synopsis
We consider the random poset P(n, p) which is generated by first selecting each subset of [n]=[1, ..., n] with probability p and then ordering the selected subsets by inclusion. We give asymptotic estimates of the size of the maximum antichain for arbitrary p= p(n). In particular, we prove that if pnΓlog n Γ , an analogue of Sperner's theorem holds: almost surely the maximum antichain is (to first order) no larger than the antichain which is obtained by selecting all elements of P(n, p) with cardinality wnΓ2x. This is almost surely not the case if pn Γ % .
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