Vertices of a cube - Iran NMO 2007 - Problem2
Source:
September 22, 2010
geometry3D geometrycombinatorics unsolvedcombinatorics
Problem Statement
Two vertices of a cube are such that is the diagonal of one its faces. A run is a sequence of vertices of the cube such that each consecutive vertices in the sequence are ends of one side of the cube. Is the runs from to itself less than runs from to or more than it?