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Source labels openChecked July 26, 2026

Erdős ProblemsNumber theory

Erdős Problem 891: Weisenberg

Weisenberg has observed that Dickson's conjecture implies the answer is no if we replace p1pkp_1\cdots p_k with p1pk1p_1\cdots p_k-1. Indeed, let LkL_k be the lowest common multiple of all integers at most p1pkp_1\cdots p_k. By Dickson's conjecture [Wikipedia], th...

Mathematical statement

Weisenberg has observed that Dickson's conjecture implies the answer is no if we replace p1pkp_1\cdots p_k with p1pk1p_1\cdots p_k-1. Indeed, let LkL_k be the lowest common multiple of all integers at most p1pkp_1\cdots p_k. By Dickson's conjecture [Wikipedia], there are infinitely many nn' such that Lkmn+1\frac{L_k}{m}n'+1 is prime for all 1m<p1pk1\leq m < p_1\cdots p_k. It follows that, if n=Lkn+1n=L_kn'+1, then all integers in [n,n+p1pk1)[n,n+p_1\cdots p_k-1) have at most kk 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_891.variants.weisenberg

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_891.variants.weisenberg (k : ) (hk : k  2) :    ᶠ n in atTop,       m  Ico n (n + (∏ i  range k, i.nth Nat.Prime) - 1),      ω m  k := 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