compare no of ways for 2 paths along surface of cube
Source: Switzerland - 2012 Swiss MO Final Round p8
January 14, 2023
combinatoricscombinatorial geometrygeometry3D geometry
Problem Statement
Consider a cube and two of its vertices and , which are the endpoints of a face diagonal. A path is a sequence of cube angles, each step of one angle along a cube edge is walked to one of the three adjacent angles. Let be the number of paths of length that starts at point and ends at and let b be the number of ways of length that starts in and ends in . Decide which of the two numbers and is the larger.