| Step | Hyp | Ref
| Expression |
| 1 | | sikeq 4242 |
. . 3
⊢ (x = A →
SIk x = SIk A) |
| 2 | 1 | eleq1d 2419 |
. 2
⊢ (x = A → (
SIk x ∈ V ↔ SIk A ∈
V)) |
| 3 | | ax-si 4084 |
. . 3
⊢ ∃y∀z∀w(⟪{z},
{w}⟫ ∈ y ↔
⟪z, w⟫ ∈
x) |
| 4 | | inss1 3476 |
. . . . . . . 8
⊢
((1c ×k 1c)
∩ y) ⊆ (1c ×k
1c) |
| 5 | | sikss1c1c 4268 |
. . . . . . . 8
⊢ SIk x ⊆
(1c ×k
1c) |
| 6 | 4, 5 | sikexlem 4296 |
. . . . . . 7
⊢
(((1c ×k 1c)
∩ y) = SIk x ↔ ∀z∀w(⟪{z},
{w}⟫ ∈ ((1c ×k
1c) ∩ y) ↔
⟪{z}, {w}⟫ ∈ SIk x)) |
| 7 | | vex 2863 |
. . . . . . . . . . . 12
⊢ z ∈
V |
| 8 | 7 | snel1c 4141 |
. . . . . . . . . . 11
⊢ {z} ∈
1c |
| 9 | | vex 2863 |
. . . . . . . . . . . 12
⊢ w ∈
V |
| 10 | 9 | snel1c 4141 |
. . . . . . . . . . 11
⊢ {w} ∈
1c |
| 11 | | snex 4112 |
. . . . . . . . . . . 12
⊢ {z} ∈
V |
| 12 | | snex 4112 |
. . . . . . . . . . . 12
⊢ {w} ∈
V |
| 13 | 11, 12 | opkelxpk 4249 |
. . . . . . . . . . 11
⊢ (⟪{z}, {w}⟫
∈ (1c
×k 1c) ↔ ({z} ∈
1c ∧ {w} ∈
1c)) |
| 14 | 8, 10, 13 | mpbir2an 886 |
. . . . . . . . . 10
⊢ ⟪{z}, {w}⟫
∈ (1c
×k 1c) |
| 15 | | elin 3220 |
. . . . . . . . . 10
⊢ (⟪{z}, {w}⟫
∈ ((1c
×k 1c) ∩ y) ↔ (⟪{z}, {w}⟫
∈ (1c
×k 1c) ∧ ⟪{z},
{w}⟫ ∈ y)) |
| 16 | 14, 15 | mpbiran 884 |
. . . . . . . . 9
⊢ (⟪{z}, {w}⟫
∈ ((1c
×k 1c) ∩ y) ↔ ⟪{z}, {w}⟫
∈ y) |
| 17 | 7, 9 | opksnelsik 4266 |
. . . . . . . . 9
⊢ (⟪{z}, {w}⟫
∈ SIk x ↔ ⟪z, w⟫
∈ x) |
| 18 | 16, 17 | bibi12i 306 |
. . . . . . . 8
⊢ ((⟪{z}, {w}⟫
∈ ((1c
×k 1c) ∩ y) ↔ ⟪{z}, {w}⟫
∈ SIk x) ↔ (⟪{z}, {w}⟫
∈ y
↔ ⟪z, w⟫ ∈
x)) |
| 19 | 18 | 2albii 1567 |
. . . . . . 7
⊢ (∀z∀w(⟪{z},
{w}⟫ ∈ ((1c ×k
1c) ∩ y) ↔
⟪{z}, {w}⟫ ∈ SIk x) ↔ ∀z∀w(⟪{z},
{w}⟫ ∈ y ↔
⟪z, w⟫ ∈
x)) |
| 20 | 6, 19 | bitri 240 |
. . . . . 6
⊢
(((1c ×k 1c)
∩ y) = SIk x ↔ ∀z∀w(⟪{z},
{w}⟫ ∈ y ↔
⟪z, w⟫ ∈
x)) |
| 21 | 20 | biimpri 197 |
. . . . 5
⊢ (∀z∀w(⟪{z},
{w}⟫ ∈ y ↔
⟪z, w⟫ ∈
x) → ((1c
×k 1c) ∩ y) = SIk x) |
| 22 | | 1cex 4143 |
. . . . . . 7
⊢
1c ∈
V |
| 23 | 22, 22 | xpkex 4290 |
. . . . . 6
⊢
(1c ×k 1c)
∈ V |
| 24 | | vex 2863 |
. . . . . 6
⊢ y ∈
V |
| 25 | 23, 24 | inex 4106 |
. . . . 5
⊢
((1c ×k 1c)
∩ y) ∈ V |
| 26 | 21, 25 | syl6eqelr 2442 |
. . . 4
⊢ (∀z∀w(⟪{z},
{w}⟫ ∈ y ↔
⟪z, w⟫ ∈
x) → SIk x ∈
V) |
| 27 | 26 | exlimiv 1634 |
. . 3
⊢ (∃y∀z∀w(⟪{z},
{w}⟫ ∈ y ↔
⟪z, w⟫ ∈
x) → SIk x ∈
V) |
| 28 | 3, 27 | ax-mp 5 |
. 2
⊢ SIk x ∈
V |
| 29 | 2, 28 | vtoclg 2915 |
1
⊢ (A ∈ V → SIk A ∈
V) |