MathDB
Connected graph with 2016 vertices

Source: Turkey JBMO TST 2016 P8

May 22, 2016
combinatoricsgraph theory

Problem Statement

Let GG be a simple connected graph with 20162016 vertices and kk edges. We want to choose a set of vertices where there is no edge between them and delete all these chosen vertices (we delete both the vertices and all edges of these vertices) such that the remaining graph becomes unconnected. If we can do this task no matter how these kk edges are arranged (by making the graph connected), find the maximal value of kk.