When $t$-intersecting hypergraphs admit bounded $c$-strong colourings

Autor: Hendrey, Kevin, Illingworth, Freddie, Kamčev, Nina, Tan, Jane
Rok vydání: 2024
Předmět:
Druh dokumentu: Working Paper
Popis: The $c$-strong chromatic number of a hypergraph is the smallest number of colours needed to colour its vertices so that every edge sees at least $c$ colours or is rainbow. We show that every $t$-intersecting hypergraph has bounded $(t + 1)$-strong chromatic number, resolving a problem of Blais, Weinstein and Yoshida. In fact, we characterise when a $t$-intersecting hypergraph has large $c$-strong chromatic number for $c\geq t+2$. Our characterisation also applies to hypergraphs which exclude sunflowers with specified parameters.
Comment: 13 pages
Databáze: arXiv