Contents

Some Hypergraph Questions Suggested by a Nordic Olympiad Problem

Cecil Rousseau1, Zsolt Tuza 2
1 Department of Mathematical Sciences The University of Memphis Memphis, Tennessee, USA
2Computer and Automation Institute Hungarian Academy of Sciences Budapest, Hungary

Abstract

A problem about “nine foreign journalists” from a Nordic Mathematical Olympiad is used as the starting point for a discussion of a class of extremal problems involving hypergraphs.
Specifically, the problem is to find a sharp lower bound for the maximum degree of the hypergraph in terms of the number of (hyper)edges and their cardinalities.