Even cycles in hypergraphs

A cycle in a hypergraph is an alternating cyclic sequence A0,v0,A1,v1,…,Ak-1,vk-1,A0 of distinct edges Ai and vertices vi such that vi∈Ai∩Ai+1 for all i modulo k. In this paper, we determine the maximum number of edges in hypergraphs on n vertices containing no even cycles.