English

Hitting sets and colorings of hypergraphs

Combinatorics 2026-05-20 v3

Abstract

In this paper we study the minimal size of edges in hypergraph families that guarantees the existence of a polychromatic coloring, that is, a kk-coloring of a vertex set such that every hyperedge contains a vertex of all kk color classes. We also investigate the connection of this problem with cc-shallow hitting sets: sets of vertices that intersect each hyperedge in at least one and at most cc vertices. We determine for some hypergraph families the minimal cc for which a cc-shallow hitting set exists. We also study this problem for a special hypergraph family, which is induced by arithmetic progressions with a difference from a given set. We show connections between some geometric hypergraph families and the latter, and prove relations between the set of differences and polychromatic colorability.

Keywords

Cite

@article{arxiv.2307.12154,
  title  = {Hitting sets and colorings of hypergraphs},
  author = {Balázs Bursics and Bence Csonka and Luca Szepessy},
  journal= {arXiv preprint arXiv:2307.12154},
  year   = {2026}
}
R2 v1 2026-06-28T11:37:46.229Z