graph has got a triangle whose sides have di erent colors
Source: 12-th Hungary-Israel Mathematical Competition 2001
April 16, 2007
inductiongraph theorycombinatorics proposedcombinatorics
Problem Statement
Here denotes a simple undirected graph with vertices, denotes the complete graph with vertices, the complete bipartite graph whose components have and vertices, and a circuit with vertices. The number of edges in the graph is denoted .
The edges of are colored with colors, and every color is used.
Show that there is a triangle whose sides have different colors.