English
If a property P on CompHausLike behaves well with explicit finite coproducts and pullbacks along open embeddings, then CompHausLike P is finitary extensive.
Русский
Если свойство P над CompHausLike хорошо себя ведет по отношению к явным конечным coproducts и pullbacks по открытым вложениям, то CompHausLike P является конечносвязным экстенсивным.
LaTeX
$$$\\mathrm{FinitaryExtensive}(\\mathrm{CompHausLike}(P))$$$
Lean4
theorem finitaryExtensive
(hP' : ∀ ⦃X Y B : CompHausLike.{u} P⦄ (f : X ⟶ B) (g : Y ⟶ B) (_ : IsOpenEmbedding f), HasExplicitPullback f g) :
FinitaryExtensive (CompHausLike P) :=
have := hasPullbacksOfInclusions hP'
finitaryExtensive_of_preserves_and_reflects (compHausLikeToTop P)