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Source labels openChecked July 26, 2026

Erdős ProblemsComplex analysis

Erdős Problem 516: Limsup Ratio Eq One Of Has Fejer Gaps

Is it true that for all entire functions f = ∑ aₖzⁿₖ such that ∑' 1 / nₖ < ∞, limsup (fun r => ratio r f) atTop = 1?

Mathematical statement

Is it true that for all entire functions f = ∑ aₖzⁿₖ such that ∑' 1 / nₖ < ∞, limsup (fun r => ratio r f) atTop = 1?

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_516.variants.limsup_ratio_eq_one_of_hasFejerGaps

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_516.variants.limsup_ratio_eq_one_of_hasFejerGaps : answer(sorry)      {f : ℂ  ℂ} {n :   } (hn : HasFejerGaps n) {a :   ℂ} (ha :  n, a n  0)    (hfn :  z, HasSum (fun k => a k * z ^ n k) (f z)),    limsup (fun r => ratio r f) atTop = 1 := 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