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Source labels openChecked July 26, 2026

PapersNumber theory

Kurepa's conjecture: Gcd

An equivalent formulation in terms of the gcd of n!n! and !n!n.

Mathematical statement

An equivalent formulation in terms of the gcd of n!n! and !n!n.

Statement source: Papers statement material

Statement terms: Source-specific

Source-specific terms. Therefore does not assert reuse rights beyond attributed display.

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

kurepa_conjecture.variants.gcd

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem kurepa_conjecture.variants.gcd (n : ) : 2 < n  (n !).gcd (! n) = 2 := 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