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Source labels openChecked July 26, 2026

Erdős ProblemsNumber theory

Erdős Problem 28

If ANA ⊆ \mathbb{N} is such that A+AA + A contains all but finitely many integers then lim sup1A1A(n)=\limsup 1_A ∗ 1_A(n) = \infty.

Mathematical statement

If ANA ⊆ \mathbb{N} is such that A+AA + A contains all but finitely many integers then lim sup1A1A(n)=\limsup 1_A ∗ 1_A(n) = \infty.

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_28

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_28 (A : Set ) (h : (A + A)ᶜ.Finite) :    limsup (fun (n : ) => (sumRep A n : ∞)) atTop = (⊤ : ∞) := 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