Coloring problem
Source: Indian Postal Coaching 2005
October 27, 2005
combinatorics unsolvedcombinatorics
Problem Statement
Consider the points =, = , = , = in the -plane. Let be four finite sets of colours(not necessarily distinct nor disjoint). In how many ways can be coloured bu colours in respectively if adjacent points have to get different colours? In how many ways can be coloured by colours in respectively if adjacent points have to get different colors?