Two Results on Union-Closed Families
Combinatorics
2017-08-07 v1
Abstract
We show that there is some absolute constant , such that for any union-closed family , if \mbox{}, then there is some element that appears in at least half of the sets of . We also show that for any union-closed family , the number of sets which are not in that cover a set in is at most , and provide examples where the inequality is tight.
Keywords
Cite
@article{arxiv.1708.01434,
title = {Two Results on Union-Closed Families},
author = {Ilan Karpas},
journal= {arXiv preprint arXiv:1708.01434},
year = {2017}
}
Comments
13 pages