May 14, 2013

Problem of the Week

for Tuesday, May 14, 2013

Below you see the complete graph of order six (K6). It is composed of six vertices and fifteen edges. The minimum crossing number for the edges is three. The crossing points are circled below. What is the number of edges in the K7 graph? What is the minimum number of edge crossings in the graph? Include a complete graph of order seven in your solution.

Winners of the K7 challenge