KöMaL 2026 K916
In a football league, 18 teams play a round-robin tournament (every team plays against every other team exactly once). The tournament is organized in rounds, meaning that in each round, every team plays against one of the other teams. Prove that after the eighth round there will be three teams such that none of these teams has played with the other two teams.
Official text KöMaL. Quoted with source.
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