| Step | Hyp | Ref
 | Expression | 
| 1 |   | pwadjoin 4120 | 
. 2
⊢ ℘(A ∪
{X}) = (℘A ∪
{a ∣
∃b ∈ ℘ Aa = (b ∪ {X})}) | 
| 2 |   | simp3 957 | 
. . 3
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
℘A
∈ N) | 
| 3 |   | simp1r 980 | 
. . . 4
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
N ∈ Nn ) | 
| 4 |   | simp2r 982 | 
. . . . 5
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
X ∈ ∼
A) | 
| 5 |   | unipw 4118 | 
. . . . . 6
⊢ ∪℘A = A | 
| 6 | 5 | compleqi 3245 | 
. . . . 5
⊢  ∼ ∪℘A = ∼ A | 
| 7 | 4, 6 | syl6eleqr 2444 | 
. . . 4
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
X ∈ ∼
∪℘A) | 
| 8 |   | nnadjoin 4521 | 
. . . 4
⊢ ((N ∈ Nn ∧ ℘A ∈ N ∧ X ∈ ∼ ∪℘A) →
{a ∣
∃b ∈ ℘ Aa = (b ∪ {X})}
∈ N) | 
| 9 | 3, 2, 7, 8 | syl3anc 1182 | 
. . 3
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
{a ∣
∃b ∈ ℘ Aa = (b ∪ {X})}
∈ N) | 
| 10 |   | elcomplg 3219 | 
. . . . . . . . 9
⊢ (X ∈ ∼ A → (X
∈ ∼ A
↔ ¬ X ∈ A)) | 
| 11 | 10 | ibi 232 | 
. . . . . . . 8
⊢ (X ∈ ∼ A → ¬ X
∈ A) | 
| 12 | 4, 11 | syl 15 | 
. . . . . . 7
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
¬ X ∈
A) | 
| 13 |   | snssg 3845 | 
. . . . . . . 8
⊢ (X ∈ ∼ A → (X
∈ A
↔ {X} ⊆ A)) | 
| 14 | 4, 13 | syl 15 | 
. . . . . . 7
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
(X ∈
A ↔ {X} ⊆ A)) | 
| 15 | 12, 14 | mtbid 291 | 
. . . . . 6
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
¬ {X} ⊆ A) | 
| 16 | 15 | intnand 882 | 
. . . . 5
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
¬ (b ⊆ A ∧ {X} ⊆ A)) | 
| 17 | 16 | ralrimivw 2699 | 
. . . 4
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
∀b
∈ ℘
A ¬ (b ⊆ A ∧ {X} ⊆ A)) | 
| 18 |   | disjr 3593 | 
. . . . 5
⊢ ((℘A ∩
{a ∣
∃b ∈ ℘ Aa = (b ∪ {X})}) =
∅ ↔ ∀t ∈ {a ∣ ∃b ∈ ℘ Aa = (b ∪
{X})} ¬ t ∈ ℘A) | 
| 19 |   | eqeq1 2359 | 
. . . . . . 7
⊢ (a = t →
(a = (b
∪ {X}) ↔ t = (b ∪
{X}))) | 
| 20 | 19 | rexbidv 2636 | 
. . . . . 6
⊢ (a = t →
(∃b
∈ ℘
Aa =
(b ∪ {X}) ↔ ∃b ∈ ℘ At = (b ∪ {X}))) | 
| 21 | 20 | ralab 2998 | 
. . . . 5
⊢ (∀t ∈ {a ∣ ∃b ∈ ℘ Aa = (b ∪
{X})} ¬ t ∈ ℘A ↔
∀t(∃b ∈ ℘ At = (b ∪
{X}) → ¬ t ∈ ℘A)) | 
| 22 |   | ralcom4 2878 | 
. . . . . 6
⊢ (∀b ∈ ℘ A∀t(t = (b ∪ {X})
→ ¬ t ∈ ℘A) ↔ ∀t∀b ∈ ℘ A(t = (b ∪ {X})
→ ¬ t ∈ ℘A)) | 
| 23 |   | vex 2863 | 
. . . . . . . . . 10
⊢ b ∈
V | 
| 24 |   | snex 4112 | 
. . . . . . . . . 10
⊢ {X} ∈
V | 
| 25 | 23, 24 | unex 4107 | 
. . . . . . . . 9
⊢ (b ∪ {X})
∈ V | 
| 26 |   | eleq1 2413 | 
. . . . . . . . . 10
⊢ (t = (b ∪
{X}) → (t ∈ ℘A ↔
(b ∪ {X}) ∈ ℘A)) | 
| 27 | 26 | notbid 285 | 
. . . . . . . . 9
⊢ (t = (b ∪
{X}) → (¬ t ∈ ℘A ↔
¬ (b ∪ {X}) ∈ ℘A)) | 
| 28 | 25, 27 | ceqsalv 2886 | 
. . . . . . . 8
⊢ (∀t(t = (b ∪
{X}) → ¬ t ∈ ℘A) ↔
¬ (b ∪ {X}) ∈ ℘A) | 
| 29 | 25 | elpw 3729 | 
. . . . . . . . 9
⊢ ((b ∪ {X})
∈ ℘A ↔
(b ∪ {X}) ⊆ A) | 
| 30 |   | unss 3438 | 
. . . . . . . . 9
⊢ ((b ⊆ A ∧ {X} ⊆ A) ↔ (b
∪ {X}) ⊆ A) | 
| 31 | 29, 30 | bitr4i 243 | 
. . . . . . . 8
⊢ ((b ∪ {X})
∈ ℘A ↔
(b ⊆
A ∧
{X} ⊆
A)) | 
| 32 | 28, 31 | xchbinx 301 | 
. . . . . . 7
⊢ (∀t(t = (b ∪
{X}) → ¬ t ∈ ℘A) ↔
¬ (b ⊆ A ∧ {X} ⊆ A)) | 
| 33 | 32 | ralbii 2639 | 
. . . . . 6
⊢ (∀b ∈ ℘ A∀t(t = (b ∪ {X})
→ ¬ t ∈ ℘A) ↔ ∀b ∈ ℘ A ¬ (b ⊆ A ∧ {X} ⊆ A)) | 
| 34 |   | r19.23v 2731 | 
. . . . . . 7
⊢ (∀b ∈ ℘ A(t = (b ∪ {X})
→ ¬ t ∈ ℘A) ↔ (∃b ∈ ℘ At = (b ∪ {X})
→ ¬ t ∈ ℘A)) | 
| 35 | 34 | albii 1566 | 
. . . . . 6
⊢ (∀t∀b ∈ ℘ A(t = (b ∪ {X})
→ ¬ t ∈ ℘A) ↔ ∀t(∃b ∈ ℘ At = (b ∪ {X})
→ ¬ t ∈ ℘A)) | 
| 36 | 22, 33, 35 | 3bitr3ri 267 | 
. . . . 5
⊢ (∀t(∃b ∈ ℘ At = (b ∪ {X})
→ ¬ t ∈ ℘A) ↔ ∀b ∈ ℘ A ¬ (b ⊆ A ∧ {X} ⊆ A)) | 
| 37 | 18, 21, 36 | 3bitri 262 | 
. . . 4
⊢ ((℘A ∩
{a ∣
∃b ∈ ℘ Aa = (b ∪ {X})}) =
∅ ↔ ∀b ∈ ℘ A ¬ (b ⊆ A ∧ {X} ⊆ A)) | 
| 38 | 17, 37 | sylibr 203 | 
. . 3
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
(℘A
∩ {a ∣ ∃b ∈ ℘ Aa = (b ∪
{X})}) = ∅) | 
| 39 |   | eladdci 4400 | 
. . 3
⊢ ((℘A ∈ N ∧ {a ∣ ∃b ∈ ℘ Aa = (b ∪
{X})} ∈
N ∧ (℘A ∩
{a ∣
∃b ∈ ℘ Aa = (b ∪ {X})}) =
∅) → (℘A ∪
{a ∣
∃b ∈ ℘ Aa = (b ∪ {X})})
∈ (N
+c N)) | 
| 40 | 2, 9, 38, 39 | syl3anc 1182 | 
. 2
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
(℘A
∪ {a ∣ ∃b ∈ ℘ Aa = (b ∪
{X})}) ∈
(N +c N)) | 
| 41 | 1, 40 | syl5eqel 2437 | 
1
⊢ (((M ∈ Nn ∧ N ∈ Nn ) ∧ (A ∈ M ∧ X ∈ ∼ A) ∧ ℘A ∈ N) →
℘(A
∪ {X}) ∈ (N
+c N)) |