{ "domain": "mathematics", "topics": [ "graph-theory", "combinatorics" ], "type": "proof", "also": [ "construction" ], "source": { "key": "erdos", "name": "Erdős Problems", "url": "https://www.erdosproblems.com/86", "id": "86", "curator": "Thomas Bloom", "poser": "Paul Erdős", "status": "open, $100 prize", "as_of": "2026-10-20", "prize": "$100", "catalog": "0521c19bbd38" }, "review": true, "approval": "first-time" }