English

Directed graphs without rainbow stars

Combinatorics 2024-02-05 v1

Abstract

In a rainbow version of the classical Tur\'an problem one considers multiple graphs on a common vertex set, thinking of each graph as edges in a distinct color, and wants to determine the minimum number of edges in each color which guarantees existence of a rainbow copy (having at most one edge from each graph) of a given graph. Here, we prove an optimal solution for this problem for any directed star and any number of colors.

Keywords

Cite

@article{arxiv.2402.01028,
  title  = {Directed graphs without rainbow stars},
  author = {Daniel Gerbner and Andrzej Grzesik and Cory Palmer and Magdalena Prorok},
  journal= {arXiv preprint arXiv:2402.01028},
  year   = {2024}
}
R2 v1 2026-06-28T14:35:16.123Z