Source labels openChecked July 26, 2026

Carmichael's totient function conjecture

Carmichael's totient function conjecture*: For every positive natural number $n$ , there exists a natural number $m$ with $m ≠ n$ , such that $φ(n) = φ(m)$ .

Number theory AMS 11

Mathematical statement

Carmichael's totient function conjecture*: For every positive natural number $n$ , there exists a natural number $m$ with $m ≠ n$ , such that $φ(n) = φ(m)$ .

Statement source: Wikipedia statement material

Statement terms: CC-BY-SA-4.0

Attributed source material. Reuse must follow the linked attribution and share-alike terms.

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

charmichaelTotient

Canonical source

Complete statement target, proof intentionally absentLean 4

theorem charmichaelTotient :    ∀ ⦃n : ℕ⦄, 0 < n → CarmichaelTotientFor 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

Pinned Formal Conjectures sourceformalization Wikipediabackground