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Source labels openChecked July 26, 2026

Erdős ProblemsNumber theory

Erdős Problem 52

Let AA be a finite set of integers. Is it true that for every ϵ>0\epsilon>0 max(A+A,AA)ϵA2ϵ?\max( \lvert A+A\rvert,\lvert AA\rvert)\gg_\epsilon \lvert A\rvert^{2-\epsilon}?

Mathematical statement

Let AA be a finite set of integers. Is it true that for every ϵ>0\epsilon>0 max(A+A,AA)ϵA2ϵ?\max( \lvert A+A\rvert,\lvert AA\rvert)\gg_\epsilon \lvert A\rvert^{2-\epsilon}?

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_52

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_52 : answer(sorry)   (ε : ), 0 < ε  ε < 1   (C : ), 0 < C   (A : Finset ),    (max (A + A).card (A * A).card : )  C * (A.card : ) ^ (2 - ε) := 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