All open problems
Source labels openChecked July 26, 2026

Erdős ProblemsNumber theory

Erdős Problem 389

Is it true that for every n1n \geq 1 there is a kk such that n(n+1)(n+k1)(n+k)(n+2k1)?n(n + 1) \cdots (n + k - 1) \mid (n + k) \cdots (n + 2k - 1)?

Mathematical statement

Is it true that for every n1n \geq 1 there is a kk such that

n(n+1)(n+k1)(n+k)(n+2k1)? n(n + 1) \cdots (n + k - 1) \mid (n + k) \cdots (n + 2k - 1)?

Statement source: Erdős Problems 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

erdos_389

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_389 : answer(sorry)      n  1,  k  1, ∏ i  Finset.range k, (n + i) ∣ ∏ i  Finset.range k, (n + k + i) := 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