Erdős Problem 694: Carmichael
Carmichael has asked whether there is an integer for which has exactly one solution, that is \frac{f_\max(n)}{f_\min(n)} = 1.
Mathematical statement
Carmichael has asked whether there is an integer for which has exactly one solution, that is \frac{f_\max(n)}{f_\min(n)} = 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_694.variants.carmichael
theorem erdos_694.variants.carmichael : answer(sorry) ↔ ∃ n > 0, ∃! m, Nat.totient m = n := 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