On the weak chromatic number of random hypergraphs

Autor: Dmitry A. Shabanov, Alexander N. Semenov
Rok vydání: 2020
Předmět:
Zdroj: Discrete Applied Mathematics. 276:134-154
ISSN: 0166-218X
DOI: 10.1016/j.dam.2019.03.025
Popis: The paper deals with weak chromatic numbers of random hypergraphs. Recall that a vertex coloring is said to be j -proper for a hypergraph if every j + 1 vertices of any edge do not share a common color. The j -chromatic number of a hypergraph is the minimum number of colors required for a j -proper coloring. We study the j -chromatic number of a random hypergraph in the binomial model H ( n , k , p ) in the case j = k − 2 and investigate, for fixed r , the threshold for the property that ( k − 2 ) -chromatic number of H ( n , k , p ) does not exceed r . This threshold corresponds to the sparse case, when p = c n ∕ n k for a fixed parameter c > 0 and the main result gives the tight bounds for it.
Databáze: OpenAIRE