English
IsRadical (radical a) is radical (redundant statement).
Русский
IsRadical (radical a) является радикальным (избыточное утверждение).
LaTeX
$$$ IsRadical(\operatorname{radical}(a)) $$$
Lean4
theorem isRadical_radical : IsRadical (radical a) := by
intro n p ha
rw [radical]
apply Finset.prod_dvd_of_isRelPrime
· exact pairwise_primeFactors_isRelPrime
intro i hi
simp only [mem_primeFactors] at hi
have : i ∣ radical a := by
rw [dvd_radical_iff_of_irreducible]
· exact dvd_of_mem_normalizedFactors hi
· exact irreducible_of_normalized_factor i hi
· rintro rfl
simp only [normalizedFactors_zero, Multiset.notMem_zero] at hi
exact (prime_of_normalized_factor i hi).isRadical n p (this.trans ha)