ISL 1999 A4
Prove that the set of positive integers cannot be partitioned into three nonempty subsets such that, for any two integers taken from two different subsets, the number belongs to the third subset.
Attachments:
Dataset text AI-MO AoPS. Quoted with source.
Solutions
No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.
Similar problems
These problems have the most words in common with this statement.