Each positive integer shall be coloured red or green
Source: Germany Bundeswettbewerb Mathematik 2007, Round 1, Problem 2
July 18, 2008
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Problem Statement
Each positive integer shall be coloured red or green such that it satisfies the following properties:
- The sum of three not necessarily distinct red numbers is a red number.
- The sum of three not necessarily distinct green numbers is a green number.
- There are red and green numbers.
Find all such colorations!