Edge-colorings of K-m,K-n which Forbid Multicolored Cycles

Abstract

A subgraph in an edge-colored graph is multicolored if all its edges receive distinct colors. In this paper, we study the proper edge-colorings of the complete bipartite graph K-m,K-n which forbid multicolored cycles. Mainly, we prove that (1) for any integer k >= 2, if n >= 5k - 6, then any properly n-edge-colored K-k,K-n contains a multicolored C-2k, and (2) determine the order of the properly edge-colored complete bipartite graphs which forbid multicolored C-6.