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PapersNumber theory

Kurepa's conjecture

Kurepa's conjecture

Mathematical statement

Kurepa's conjecture

For all nn, !n≢0modn!n\not\equiv 0 \mod n

This appears as B44 "Sums of factorials." in Unsolved Problems in Number Theory by Richard K. Guy

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

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem kurepa_conjecture (n : ) (h_n : 2 < n) : (!n : ) % n  0 := 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