rintro ⟨i, hi⟩
case mpr
ι : Type u_1
inst✝² : Fintype ι
inst✝¹ : DecidableEq ι
inst✝ : Encodable ι
α : Type u_2
f : ι → Option α
⊢ (∃ i, f i = none) → ∃ i, f (fintypeEquivFin.symm i) = none
case mpr.intro
ι : Type u_1
inst✝² : Fintype ι
inst✝¹ : DecidableEq ι
inst✝ : Encodable ι
α : Type u_2
f : ι → Option α
i : ι
hi : f i = none
⊢ ∃ i, f (fintypeEquivFin.symm i) = none