$s$-almost $t$-intersecting families for finite sets
Combinatorics
2026-01-13 v4
Abstract
A family of -subsets of an -set is called -almost -intersecting if each member is -disjoint with at most members. In this paper, we prove that, if is maximum, then consists of all -subsets containing a fixed -subset. Consequently, it is natural to consider the maximum-sized with . The famous Hilton-Milner theorem settles the case where is -intersecting. We characterize the remaining case completely.
Keywords
Cite
@article{arxiv.2410.20185,
title = {$s$-almost $t$-intersecting families for finite sets},
author = {Dehai Liu and Kaishun Wang and Tian Yao},
journal= {arXiv preprint arXiv:2410.20185},
year = {2026}
}