English
A semilocal ring is Noetherian if all localizations at maximal ideals are Noetherian.
Русский
Полусемильное кольцо конечно, если все локализации по максимальным идеалам конечно порожденны.
LaTeX
$$$\\text{IsNoetherianRing}(R) \\Leftarrow \\forall P [P.IsMaximal], \\text{IsNoetherianRing}(R_p)$$$
Lean4
/-- A semilocal ring `R` is Noetherian if
its localization at every maximal ideal is a Noetherian ring. -/
theorem of_isLocalization_maximal (H : ∀ (P : Ideal R) [P.IsMaximal], IsNoetherianRing (Rₚ P)) : IsNoetherianRing R
where
noetherian
N :=
Submodule.fg_of_isLocalized_maximal Rₚ Rₚ (fun P _ => Algebra.linearMap R (Rₚ P)) N fun _ _ ↦
IsNoetherian.noetherian _