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Source labels openChecked July 26, 2026

Erdős ProblemsNumber theory

Erdős Problem 291: Shiu Heuristic Density Zero

In particular, there should be infinitely many nn, but the set of such nn should have density zero. Unfortunately this heuristic is difficult to turn into a proof.

Mathematical statement

In particular, there should be infinitely many nn, but the set of such nn should have density zero. Unfortunately this heuristic is difficult to turn into a proof.

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_291.variants.shiu_heuristic_density_zero

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_291.variants.shiu_heuristic_density_zero :    Filter.Tendsto (fun N :        ((((Finset.Icc 1 N).filter (fun n  Nat.gcd (a n) (L n) = 1)).card : ) / (N : )))      atTop (nhds 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