Let 2 [n] be the poset of all subsets of a set with n elements ordered by inclusion. A long chain in this poset is a chain of n&1 subsets starting with a subset with one element and ending with a subset with n&1 elements. In this paper we prove: Given any collection of at most n&2 skipless chains in
The t-intersection Problem in the Truncated Boolean Lattice
β Scribed by Rudolf Ahlswede; Christian Bey; Konrad Engel; Levon H. Khachatrian
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 146 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0195-6698
No coin nor oath required. For personal study only.
β¦ Synopsis
Let I (n, t) be the class of all t-intersecting families of subsets of [n] and set
β€k . After the maximal families in I (n, t) [13] and in I k (n, t) [1,9] are known we study now maximal families in I β€k (n, t). We present a conjecture about the maximal cardinalities and prove it in several cases.
More generally cardinalities are replaced by weights and asymptotic estimates are given. Analogous investigations are made for I (n, t) β© C(n, s), where C(n, s) is the class of all s-cointersecting families of subsets of [n]. In particular we establish an asymptotic form of a conjecture by Bang et al. [4].
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