English
Irreducible (Associates.mk a) is equivalent to Irreducible a.
Русский
Неразложимость (Associates.mk a) эквивалентна неразложимости a.
LaTeX
$$$ \operatorname{Irreducible}(\mathrm{mk}(a)) \iff \operatorname{Irreducible}(a) $$$
Lean4
@[simp]
theorem mk_dvdNotUnit_mk_iff {a b : M} : DvdNotUnit (Associates.mk a) (Associates.mk b) ↔ DvdNotUnit a b :=
by
simp only [DvdNotUnit, mk_ne_zero, mk_surjective.exists, isUnit_mk, mk_mul_mk, mk_eq_mk_iff_associated,
Associated.comm (x := b)]
refine Iff.rfl.and ?_
constructor
· rintro ⟨x, hx, u, rfl⟩
refine ⟨x * u, ?_, mul_assoc ..⟩
simpa
· rintro ⟨x, ⟨hx, rfl⟩⟩
use x