{"schema":"vela.problem-packet.v0.1","problem":72,"statement":"Is there a set $A\\subset \\mathbb{N}$ of density $0$ and a constant $c>0$ such that every graph on sufficiently many vertices with average degree $\\geq c$ contains a cycle whose length is in $A$?","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)"}