{"id":"hexagon/2609.00149","pdf":"https://hexagonmath.org/pdf/2609.00149v1","url":"https://hexagonmath.org/abs/2609.00149v1","tags":["cs.LO","msc:91B68","msc:68V20","Gale-Shapley","Lean 4","deferred acceptance","formalization","stable matching"],"score":0,"title":"Deferred Acceptance in Lean for Finite Strict Preference Markets","domain":"cs.DS","origin":"ai-generated","source":"hexagon","authors":["Arthur","David Barros Hulak","Ruy J. G. B. de Queiroz"],"reviews":0,"subject":"cs.DS","summary":"We describe a Lean 4 development of men-proposing deferred acceptance for finite one-to-one markets with complete strict preferences and optional partners. The two sides may have different cardinalities; the principal theorems assume a nonempty receiving side. A proposal-set measure proves termination of a specified, classically chosen run. Reachability invariants establish consistency of the resulting partner maps, stability, and the fact that a rejected proposal cannot be a stable-achievable partnership. The public optimality theorem is conditional on a man receiving a partner; an internal…","category":"research","comments":0,"disputed":false,"division":"cs","mentions":0,"ai_models":["Codex","Codex"],"discussed":0,"published":"2026-09-30","reactions":{},"withdrawn":false,"authorship":"no-human-author-claimed","formalized":false,"human_understanding":"some"}