{"schema":"vela.problem-packet.v0.1","problem":321,"statement":"What is the size of the largest $A\\subseteq \\{1,\\ldots,N\\}$ such that all sums $\\sum_{n\\in S}\\frac{1}{n}$ are distinct for $S\\subseteq A$?","status":"open","seam":"raw","closureRoutes":[],"obligations":[],"attestations":[],"attempts":[{"id":"att_91844ffcbadd827f","kind":"dead_end","claim":"attempted via frontier 'sidon/B2' (transfer_strength=weak) -> no_progress","grade":"honest_null","gateStatus":"needs_verification","superseded":false}],"velaLean":[],"oeis":[{"id":"A384927","name":"a(n) is the maximum size of a subset S of {1, 2, ..., n} such that for any distinct elements t, u in S, t + u does not divide t*u.","terms":"1,2,3,4,5,5,6,7,8,9,10,10,11,12,12,13,14,14,15,15,16,17,18,18,19,20,21,21,22,23,24,25,26,27,27,28,29,30,31,31,32,32,33,3","url":"https://oeis.org/A384927"},{"id":"A391592","name":"Maximum size of a subset S of {1..n} such that all subset sums of {1/k : k in S} are distinct.","terms":"1,2,3,4,5,5,6,7,8,9,10,10,11,12,12,13,14,14,15,15,15,16,17,17,18,19,20,20,21,21,22,23,23,24,24,25,26,27,28,28,29,29,30,3","url":"https://oeis.org/A391592"}],"generated_note":"derived view; the signed event log is the source of truth (vela check / vela reproduce)"}