{
  "domain": "mathematics",
  "topics": [
    "probability",
    "algebra"
  ],
  "type": "construction",
  "also": [
    "proof"
  ],
  "source": {
    "key": "green-100",
    "name": "Ben Green's 100 open problems",
    "url": "https://people.maths.ox.ac.uk/greenbj/papers/open-problems.pdf#problem.28",
    "id": "28",
    "curator": "Ben Green",
    "poser": "Emmanuel Amiot",
    "status": "open",
    "as_of": "2026-10-20",
    "catalog": "0521c19bbd38"
  }
}