The Upper Chromatic Number of the Cartesian Product of Co-Hypergraphs
Zheng Qing-yu · Mathematica Applicata · 2002
The notion of mixed hypergraphs was introduced by Vitaly I.Voloshin in 1995,it is a generalization of the notion of hypergraphs.The lower chromatic number and the upper chromatic number of a mixed hypergraph are both importment.This paper discusses the upper chromatic number of the Cartesian product of co-hypergraphs.