exact Bijective.finite_iff (f := fun i ↦ ⟨⟨i,i.2.1⟩, i.2.2⟩)
  ⟨by rintro ⟨i, hi⟩ ⟨j, hj⟩ hij; simpa using hij, by rintro ⟨⟨i,his⟩, hi⟩; use ⟨i, ⟨his, hi⟩⟩⟩
case h.e'_2.h.e'_1.h.a
α : Type u_1
β : Type u_2
ι : Type u_3
s✝ : Set α
n : ℕ∞
f g : α → ℕ∞
s : Set α
⊢ Finite ↑(s ∩ support f) ↔ Finite ↑(support fun a => f ↑a)
no goals