LehmerTotient.lean`

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Project sources: Pinned project documentation, Formal Conjectures paper, arXiv v1

1 declarations, 1 contain sorry, 0 declared as axioms

Lehmer's totient problem

Reference: Wikipedia

Imports (1)

FormalConjecturesUtil

theorem LehmerTotient.lehmer_totient Does there exist a composite number $n > 1$ such that Euler’s totient function $\varphi(n)$ divides $n - 1$? sorry line 35 source
Source documentation
Does there exist a composite number $n > 1$ such that Euler’s totient function $\varphi(n)$ divides $n - 1$?

depends on sorry what this means
Statement uses: Iff, True, Exists, Nat, And, GT.gt, OfNat.ofNat, Not, Prime, Dvd.dvd, Nat.totient, HSub.hSub
Proof uses: sorryAx, Lean.Name, Bool.false, Lean.Name.num, Lean.Name.str, Lean.Name.anonymous
12 instances, coercions and auxiliary constants left out.

Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
```
theorem lehmer_totient :
    answer(sorry) ↔ ∃ n > 1, ¬Prime n ∧ Nat.totient n ∣ n - 1 := by
…
```