All open problems
Source labels openChecked July 26, 2026
Erdős Problem 329
Erdős Problem 329.* Let A ⊆ ℕ be a Sidon set. How large can lim sup_{N → ∞} |A ∩ {1,…,N}| / N^{1/2} be?
Mathematical statement
Erdős Problem 329.*
Let A ⊆ ℕ be a Sidon set. How large can
lim sup_{N → ∞} |A ∩ {1,…,N}| / N^{1/2}
be?
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_329
Complete statement target, proof intentionally absentLean 4
theorem erdos_329 : sSup {sidonUpperDensity A | (A : Set ℕ) (_ : IsSidon A)} = answer(sorry) := 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