English
For natural numbers a,b, the emultiplicity is unchanged by casting to integers: emultiplicity(a,b) in integers equals emultiplicity(a,b).
Русский
Для натуральных a, b эмплитичность не изменяется при приведении к целым: emultiplicity (a:ℤ) (b:ℤ) = emultiplicity a b.
LaTeX
$$$$emultiplicity\ (a:\mathbb{Z})\ (b:\mathbb{Z}) = emultiplicity\ a\ b.$$$$
Lean4
@[norm_cast]
theorem natCast_emultiplicity (a b : ℕ) : emultiplicity (a : ℤ) (b : ℤ) = emultiplicity a b :=
by
unfold emultiplicity FiniteMultiplicity
congr! <;> norm_cast