Let x0 of type ι → ο be given.
Assume H0: x0 0.
Let x1 of type ι be given.
Apply H2 with
x0 x1.
Let x2 of type ι be given.
Apply H3 with
x0 x1.
Assume H4:
x2 ∈ omega.
Apply nat_ind with
λ x3 . ∀ x4 . equip x4 x3 ⟶ x0 x4,
x2,
x1 leaving 3 subgoals.
Let x3 of type ι be given.
Apply equip_0_Empty with
x3,
λ x4 x5 . x0 x5 leaving 2 subgoals.
The subproof is completed by applying H5.
The subproof is completed by applying H0.
Let x3 of type ι be given.
Assume H6:
∀ x4 . equip x4 x3 ⟶ x0 x4.
Let x4 of type ι be given.
Apply equip_sym with
x4,
ordsucc x3,
x0 x4 leaving 2 subgoals.
The subproof is completed by applying H7.
Let x5 of type ι → ι be given.
Apply bijE with
ordsucc x3,
x4,
x5,
x0 x4 leaving 2 subgoals.
The subproof is completed by applying H8.
Assume H9:
∀ x6 . x6 ∈ ordsucc x3 ⟶ x5 x6 ∈ x4.
Assume H10:
∀ x6 . x6 ∈ ordsucc x3 ⟶ ∀ x7 . x7 ∈ ordsucc x3 ⟶ x5 x6 = x5 x7 ⟶ x6 = x7.
Assume H11:
∀ x6 . x6 ∈ x4 ⟶ ∃ x7 . and (x7 ∈ ordsucc x3) (x5 x7 = x6).
Apply set_ext with
x4,
binunion {x5 x6|x6 ∈ x3} (Sing (x5 x3)),
λ x6 x7 . x0 x7 leaving 3 subgoals.
Let x6 of type ι be given.
Assume H13: x6 ∈ x4.
Apply H11 with
x6,
x6 ∈ binunion (prim5 x3 x5) (Sing (x5 x3)) leaving 2 subgoals.
The subproof is completed by applying H13.
Let x7 of type ι be given.
Assume H14:
(λ x8 . and (x8 ∈ ordsucc x3) (x5 x8 = x6)) x7.
Apply H14 with
x6 ∈ binunion (prim5 x3 x5) (Sing (x5 x3)).
Assume H16: x5 x7 = x6.
Apply ordsuccE with
x3,
x7,
x6 ∈ binunion (prim5 x3 x5) (Sing (x5 x3)) leaving 3 subgoals.
The subproof is completed by applying H15.
Assume H17: x7 ∈ x3.
Apply binunionI1 with
prim5 x3 x5,
Sing (x5 x3),
x6.
Apply H16 with
λ x8 x9 . x8 ∈ {x5 x10|x10 ∈ x3}.
Apply ReplI with
x3,
x5,
x7.
The subproof is completed by applying H17.
Assume H17: x7 = x3.
Apply binunionI2 with
prim5 x3 x5,
Sing (x5 x3),
x6.
Apply H16 with
λ x8 x9 . x8 ∈ Sing (x5 x3).
Apply H17 with
λ x8 x9 . x5 x9 ∈ Sing (x5 x3).
The subproof is completed by applying SingI with x5 x3.
Let x6 of type ι be given.
Assume H13:
x6 ∈ binunion {x5 x7|x7 ∈ x3} (Sing (x5 x3)).
Apply binunionE with
{x5 x7|x7 ∈ x3},
Sing (x5 x3),
x6,
x6 ∈ x4 leaving 3 subgoals.
The subproof is completed by applying H13.
Assume H14: x6 ∈ {x5 ...|x7 ∈ x3}.