{"schema":"vela.problem-packet.v0.1","problem":199,"statement":"If $A\\subset \\mathbb{R}$ does not contain a 3-term arithmetic progression then must $\\mathbb{R}\\backslash A$ contain an infinite arithmetic progression?","status":"solved","seam":"raw","closureRoutes":[],"obligations":[],"attestations":[],"attempts":[],"velaLean":[],"oeis":[],"generated_note":"derived view; the signed event log is the source of truth (vela check / vela reproduce)"}