CMI 2017 #5
Source: CMI 2017
April 26, 2018
CMIChennai Mathematical InstituteB.ScCS2017Coloring
Problem Statement
Each integer is colored with exactly one of possible colors -- black, red or white -- satisfying the following two rules : the negative of a black number must be colored white, and the sum of two white numbers (not necessarily distinct) must be colored black.(a) Show that, the negative of a white number must be colored black and the sum of two black numbers must be colored white.(b) Determine all possible colorings of the integers that satisfy these rules.