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Source labels openChecked July 26, 2026
Erdős Problem 940: Three Cubes
Is it true that the set of integers which are the sum of at most three cubes has density ?
Mathematical statement
Is it true that the set of integers which are the sum of at most three cubes has density ?
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_940.variants.three_cubes
Complete statement target, proof intentionally absentLean 4
theorem erdos_940.variants.three_cubes : answer(sorry) ↔ {n : ℕ | ∃ (S : Multiset ℕ), S.card ≤ 3 ∧ n = (Multiset.map (· ^ 3) S).sum}.HasDensity 0 := 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