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Source labels openChecked July 26, 2026

Erdős ProblemsNumber theory

Erdős Problem 931

Let k1k23k_1 \geq k_2 \geq 3. Are there only finitely many n2n1+k1n_2\geq n_1 + k_1 such that 1ik1(n1+i) and 1jk2(n2+j)\prod_{1\leq i\leq k_1}(n_1 + i)\ \text{and}\ \prod_{1\leq j\leq k_2} (n_2 + j) have the same prime factors?

Mathematical statement

Let k1k23k_1 \geq k_2 \geq 3. Are there only finitely many n2n1+k1n_2\geq n_1 + k_1 such that

1ik1(n1+i) and 1jk2(n2+j) \prod_{1\leq i\leq k_1}(n_1 + i)\ \text{and}\ \prod_{1\leq j\leq k_2} (n_2 + j)

have the same prime factors?

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_931

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_931 : answer(sorry)  ᵉ (k₁ : ) (k₂  3), k₂  k₁     { (n₁, n₂) | n₁ + k₁  n₂       (∏ i  Finset.Icc 1 k₁, (n₁ + i)).primeFactors =      (∏ j  Finset.Icc 1 k₂, (n₂ + j)).primeFactors }.Finite := 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