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GeometricallyP.Mathlib.Topology.Irreducible

theorem PreirreducibleSpace.of_forall_nonempty_inter {X : Type u_1} [TopologicalSpace X] (H : ∀ ⦃U V : Set X⦄, IsOpen UIsOpen VU.NonemptyV.Nonempty(U V).Nonempty) :
theorem IrreducibleSpace.of_openCover {X : Type u_1} {ι : Type u_2} [TopologicalSpace X] [ : Nonempty ι] {U : ιTopologicalSpace.Opens X} (hU : TopologicalSpace.IsOpenCover U) (hn : ∀ (i j : ι), ((U i).carrier (U j).carrier).Nonempty) (h : ∀ (i : ι), IrreducibleSpace (U i)) :

Irreducibility can be checked on an open cover with pairwise non-empty intersections.