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Source labels openChecked July 26, 2026

WikipediaNumber theory

Betrothed numbers

Same parity betrothed numbers conjecture.* Do there exist betrothed numbers (m,n)(m, n) where both have the same parity (both even or both odd)?

Mathematical statement

Same parity betrothed numbers conjecture.* Do there exist betrothed numbers (m,n)(m, n) where both have the same parity (both even or both odd)?

All known betrothed pairs consist of one even and one odd number.

Statement source: Wikipedia statement material

Statement terms: CC-BY-SA-4.0

Attributed source material. Reuse must follow the linked attribution and share-alike terms.

Statement artifacts, not proofs

These records expose exact Lean propositions and statement-only wrappers. Defining a proposition does not supply a proof of it. A placeholder-bearing target also contains no proof. Elaboration checks syntax and types; it does not certify that a formalization perfectly captures every nuance of the informal problem.

Pinned Lean formulation 1

same_parity_betrothed

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem same_parity_betrothed :    answer(sorry)   m n : , IsBetrothed m n  (Even m  Even n) := by  sorry
Statement source
Formal Conjectures
Lean version
v4.27.0
Placeholder
Present; no proof artifact
Source evidence
Pinned source index
Fidelity review
Community formulation

References