English
For any i, p prime, r ≠ 0, Not(p ∣ r) iff (p·i + r).factorization p = 0.
Русский
Пусть i, p и r — натуральные числа, p — простое, r ≠ 0. Тогда p не делит r тогда (p·i + r).factorization p = 0; и наоборот.
LaTeX
$$$ (i : \Nat) \; (pp : p.Prime) \; (hr0 : r \ne 0) : \neg p \mid r \iff (p * i + r).factorization p = 0$$$
Lean4
theorem factorization_eq_zero_iff_remainder {p r : ℕ} (i : ℕ) (pp : p.Prime) (hr0 : r ≠ 0) :
¬p ∣ r ↔ (p * i + r).factorization p = 0 :=
by
refine ⟨factorization_eq_zero_of_remainder i, fun h => ?_⟩
rw [factorization_eq_zero_iff] at h
contrapose! h
refine ⟨pp, ?_, ?_⟩
· rwa [← Nat.dvd_add_iff_right (dvd_mul_right p i)]
· contrapose! hr0
exact (add_eq_zero.1 hr0).2