English
Equivalent to the previous: for coprime a,b, (a·b).factorization = a.factorization + b.factorization.
Русский
Эквивалентно предшедшему: если a и b взаимно простые, тогда факторизация произведения равна сумме факторизаций.
LaTeX
$$$\\forall a,b:\\; (a \\cdot b).factorization = a.factorization + b.factorization \\quad (a,b \\neq 0,\\; \\gcd(a,b)=1)$$$
Lean4
/-- For coprime `a` and `b`, the power of `p` in `a * b` is the sum of the powers in `a` and `b` -/
theorem factorization_mul_of_coprime {a b : ℕ} (hab : Coprime a b) :
(a * b).factorization = a.factorization + b.factorization :=
by
ext q
rw [Finsupp.add_apply, factorization_mul_apply_of_coprime hab]