Apply unknownprop_09a15e4a4a26a9e483412f704016420ed6a01f84c815d73b065b7804e5d926a9 with
λ x0 x1 : ι → ι → ι . ∀ x2 x3 x4 . In x4 (x1 x2 x3) ⟶ and (In x4 x2) (nIn x4 x3).
Let x0 of type ι be given.
Let x1 of type ι be given.
Let x2 of type ι be given.
Assume H0:
In x2 (Sep x0 (λ x3 . nIn x3 x1)).
Apply unknownprop_d8740353ee211303fc5f492a89312f8632727f644f6079ddb4e027d2c48051cb with
x0,
λ x3 . nIn x3 x1,
x2.
The subproof is completed by applying H0.