English
For all a,b, radical(a) divides radical(b) if and only if normalizedFactors(a) is a subset of normalizedFactors(b).
Русский
Для любых a,b радикал(a) делится радикалом(b) тогда и только тогда, когда нормализованные факторы a содержатся в нормализованных факторах b.
LaTeX
$$$\operatorname{radical}(a) \mid \operatorname{radical}(b) \iff \operatorname{normalizedFactors}(a) \subseteq \operatorname{normalizedFactors}(b)$$$
Lean4
theorem radical_dvd_radical_iff_normalizedFactors_subset_normalizedFactors :
radical a ∣ radical b ↔ normalizedFactors a ⊆ normalizedFactors b :=
by
obtain rfl | ha₀ := eq_or_ne a 0
· simp
have : Nontrivial M := ⟨a, 0, ha₀⟩
rw [dvd_iff_normalizedFactors_le_normalizedFactors radical_ne_zero radical_ne_zero,
Multiset.le_iff_subset (normalizedFactors_nodup isRadical_radical)]
simp only [Multiset.subset_iff, ← mem_primeFactors, primeFactors_radical]