Let x0 of type ι be given.
Let x1 of type ι be given.
Apply H0 with
finite (binunion x0 (Sing x1)).
Let x2 of type ι be given.
Apply H1 with
finite (binunion x0 (Sing x1)).
Assume H2:
x2 ∈ omega.
Apply equip_sym with
x0,
x2,
finite (binunion x0 (Sing x1)) leaving 2 subgoals.
The subproof is completed by applying H3.
Let x3 of type ι → ι be given.
Apply bijE with
x2,
x0,
x3,
finite (binunion x0 (Sing x1)) leaving 2 subgoals.
The subproof is completed by applying H4.
Assume H5: ∀ x4 . x4 ∈ x2 ⟶ x3 x4 ∈ x0.
Assume H6: ∀ x4 . x4 ∈ x2 ⟶ ∀ x5 . x5 ∈ x2 ⟶ x3 x4 = x3 x5 ⟶ x4 = x5.
Assume H7:
∀ x4 . x4 ∈ x0 ⟶ ∃ x5 . and (x5 ∈ x2) (x3 x5 = x4).
Apply xm with
x1 ∈ x0,
finite (binunion x0 (Sing x1)) leaving 2 subgoals.
Assume H8: x1 ∈ x0.
Apply set_ext with
binunion x0 (Sing x1),
x0,
λ x4 x5 . finite x5 leaving 3 subgoals.
Let x4 of type ι be given.
Apply binunionE with
x0,
Sing x1,
x4,
x4 ∈ x0 leaving 3 subgoals.
The subproof is completed by applying H9.
Assume H10: x4 ∈ x0.
The subproof is completed by applying H10.
Assume H10:
x4 ∈ Sing x1.
Apply SingE with
x1,
x4,
λ x5 x6 . x6 ∈ x0 leaving 2 subgoals.
The subproof is completed by applying H10.
The subproof is completed by applying H8.
The subproof is completed by applying binunion_Subq_1 with
x0,
Sing x1.
The subproof is completed by applying H0.
Let x4 of type ο be given.
Apply H9 with
ordsucc x2.
Apply andI with
ordsucc x2 ∈ omega,
equip (binunion x0 (Sing x1)) (ordsucc x2) leaving 2 subgoals.
Apply omega_ordsucc with
x2.
The subproof is completed by applying H2.
Apply equip_sym with
ordsucc x2,
binunion x0 (Sing x1).
set y5 to be ...
Apply L10 with
∃ x6 : ι → ι . bij (ordsucc x2) (binunion x0 (Sing x1)) x6.
Assume H11: ∀ x6 . x6 ∈ x2 ⟶ y5 x6 = x3 x6.
Assume H12: y5 x2 = x1.
Let x6 of type ο be given.
Apply H13 with
y5.
Apply bijI with
ordsucc x2,
binunion x0 (Sing x1),
y5 leaving 3 subgoals.
Let x7 of type ι be given.
Apply ordsuccE with
x2,
x7,
y5 x7 ∈ binunion x0 (Sing x1) leaving 3 subgoals.
The subproof is completed by applying H14.
Assume H15: x7 ∈ x2.
Apply binunionI1 with
x0,
Sing x1,
y5 x7.
Apply H11 with
x7,
λ x8 x9 . x9 ∈ x0 leaving 2 subgoals.
The subproof is completed by applying H15.
Apply H5 with
x7.
The subproof is completed by applying H15.
Assume H15: x7 = x2.
Apply binunionI2 with
x0,
Sing x1,
y5 x7.
Apply H15 with
λ x8 x9 . y5 x9 ∈ Sing x1.
Apply H12 with
λ x8 x9 . x9 ∈ Sing x1.
The subproof is completed by applying SingI with x1.
Let x7 of type ι be given.