Watanabe, M., Arrow relations on families of finite sets, Discrete Mathematics 94 (1991) 53-64. Let n, m and k be positive integers. Let X be a set of cardinality n, and let 9 be a family of subsets of X. We write (n, m)-, (n -1, mk), when for all 9 with (S( em, there exists an element x of X such t
On families of finite sets with bounds on unions and intersections
β Scribed by Chang Bang; Henry Sharp Jr.; Peter Winkler
- Publisher
- Elsevier Science
- Year
- 1983
- Tongue
- English
- Weight
- 364 KB
- Volume
- 45
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
We present a conjecture, with some supporting results, concerning the maximum size of a family of subsets satisfying the following conditions: the intersection of any two members of the family has cardinal@ at least s, and the intersection of the complements of any two members has cardinal@ at least r.
π SIMILAR VOLUMES
In 1964, Kautz and Singleton (IEEE Trans. Inform. Theory 10 (1964), 363-377) introduced the superimposed code concept. A binary superimposed code of strength s is identified by the incidence matrix of a family of finite sets in which no set is covered by the union of s others (
## Abstract We show that under some conditions on a family __A__ β __I__ there exists a subfamily __A__~0~ β __A__ such that βͺ __A__~0~ is nonmeasurable with respect to a fixed ideal __I__ with Borel base of a fixed uncountable Polish space. Our result applies to the classical ideal of null subsets