English

Three-chromatic geometric hypergraphs

Combinatorics 2026-01-21 v2 Discrete Mathematics

Abstract

We prove that for any planar convex body C there is a positive integer m with the property that any finite point set P in the plane can be three-colored such that there is no translate of C containing at least m points of P, all of the same color. As a part of the proof, we show a strengthening of the Erd\H{o}s-Sands-Sauer-Woodrow conjecture. Surprisingly, the proof also relies on the two dimensional case of the Illumination conjecture.

Keywords

Cite

@article{arxiv.2112.01820,
  title  = {Three-chromatic geometric hypergraphs},
  author = {Gábor Damásdi and Dömötör Pálvölgyi},
  journal= {arXiv preprint arXiv:2112.01820},
  year   = {2026}
}

Comments

In the revised version we have removed Appendix B, which contained an incorrect proof of a footnote

R2 v1 2026-06-24T08:02:57.236Z