A 920-block explicit construction guaranteeing a triple intersection with every 6-subset of [60]
Combinatorics
2026-01-13 v1
Abstract
We present an explicit family of subsets of size of with the property that every -subset intersects at least one block in at least three elements, i.e.\ . The construction is purely combinatorial, based on a partition of the ground set into pairs and a pigeonhole argument. We also record a simple counting lower bound and discuss how different partitions of the ten base blocks affect the emergence of triple intersections.
Keywords
Cite
@article{arxiv.2601.06179,
title = {A 920-block explicit construction guaranteeing a triple intersection with every 6-subset of [60]},
author = {Paulo Henrique Cunha Gomes},
journal= {arXiv preprint arXiv:2601.06179},
year = {2026}
}