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Source labels openChecked July 26, 2026

Erdős ProblemsCombinatorics

Erdős Problem 1192

Does there exist, for all r2r\geq 2, a basis AA of order rr (so that fr(n)>0f_r(n)>0 for all large nn) such that nxfr(n)2x\sum_{n\leq x}f_r(n)^2 \ll x for all xx?

Mathematical statement

Does there exist, for all r2r\geq 2, a basis AA of order rr (so that fr(n)>0f_r(n)>0 for all large nn) such that nxfr(n)2x\sum_{n\leq x}f_r(n)^2 \ll x for all xx?

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_1192

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_1192 :    answer(sorry)        r  2,  A : Set ,        (ᶠ n in atTop, f_r A r n > 0)         (fun (x : )  ∑ n  range (x + 1), (f_r A r n : ) ^ 2) =O[atTop]          (fun (x : )  (x : )) := 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