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Coloring numbers from a set

Source: Argentina TST 2011, Problem 1

August 29, 2014
combinatorics proposedcombinatorics

Problem Statement

Each number from the set {1,2,3,4,5,6,7,8}\{1,2,3,4,5,6,7,8\} is either colored red or blue, following these rules:
a) The number 44 is colored red, and there is at least one number colored blue. b) If two numbers x,yx, y have different colors and x+y8x + y \leq 8, then the number x+yx + y is colored blue. c) If two numbers x,yx, y have different colors and xy8x \cdot y \leq 8, then the number xyx \cdot y is colored red.
Find all possible ways the numbers from this set can be colored.