| Step | Hyp | Ref
 | Expression | 
| 1 |   | elnc 6126 | 
. . . . . . . . 9
⊢ (℘1p ∈ Nc ℘1A ↔ ℘1p ≈ ℘1A) | 
| 2 |   | enpw1 6063 | 
. . . . . . . . 9
⊢ (p ≈ A
↔ ℘1p ≈ ℘1A) | 
| 3 | 1, 2 | bitr4i 243 | 
. . . . . . . 8
⊢ (℘1p ∈ Nc ℘1A ↔ p
≈ A) | 
| 4 |   | elnc 6126 | 
. . . . . . . . 9
⊢ (℘1t ∈ Nc ℘1B ↔ ℘1t ≈ ℘1B) | 
| 5 |   | enpw1 6063 | 
. . . . . . . . 9
⊢ (t ≈ B
↔ ℘1t ≈ ℘1B) | 
| 6 | 4, 5 | bitr4i 243 | 
. . . . . . . 8
⊢ (℘1t ∈ Nc ℘1B ↔ t
≈ B) | 
| 7 |   | enmap1 6075 | 
. . . . . . . . 9
⊢ (p ≈ A
→ (p ↑m
t) ≈ (A ↑m t)) | 
| 8 |   | enmap2 6069 | 
. . . . . . . . 9
⊢ (t ≈ B
→ (A ↑m
t) ≈ (A ↑m B)) | 
| 9 |   | entr 6039 | 
. . . . . . . . 9
⊢ (((p ↑m t) ≈ (A
↑m t) ∧ (A
↑m t) ≈
(A ↑m B)) → (p
↑m t) ≈
(A ↑m B)) | 
| 10 | 7, 8, 9 | syl2an 463 | 
. . . . . . . 8
⊢ ((p ≈ A
∧ t
≈ B) → (p ↑m t) ≈ (A
↑m B)) | 
| 11 | 3, 6, 10 | syl2anb 465 | 
. . . . . . 7
⊢ ((℘1p ∈ Nc ℘1A ∧ ℘1t ∈ Nc ℘1B) → (p
↑m t) ≈
(A ↑m B)) | 
| 12 |   | entr 6039 | 
. . . . . . . 8
⊢ ((g ≈ (p
↑m t) ∧ (p
↑m t) ≈
(A ↑m B)) → g
≈ (A ↑m
B)) | 
| 13 | 12 | ancoms 439 | 
. . . . . . 7
⊢ (((p ↑m t) ≈ (A
↑m B) ∧ g ≈
(p ↑m t)) → g
≈ (A ↑m
B)) | 
| 14 | 11, 13 | sylan 457 | 
. . . . . 6
⊢ (((℘1p ∈ Nc ℘1A ∧ ℘1t ∈ Nc ℘1B) ∧ g ≈ (p
↑m t)) →
g ≈ (A ↑m B)) | 
| 15 | 14 | 3impa 1146 | 
. . . . 5
⊢ ((℘1p ∈ Nc ℘1A ∧ ℘1t ∈ Nc ℘1B ∧ g ≈ (p
↑m t)) →
g ≈ (A ↑m B)) | 
| 16 | 15 | exlimivv 1635 | 
. . . 4
⊢ (∃p∃t(℘1p ∈ Nc ℘1A ∧ ℘1t ∈ Nc ℘1B ∧ g ≈ (p
↑m t)) →
g ≈ (A ↑m B)) | 
| 17 |   | cenc.1 | 
. . . . . . 7
⊢ A ∈
V | 
| 18 | 17 | pw1ex 4304 | 
. . . . . 6
⊢ ℘1A ∈
V | 
| 19 | 18 | ncelncsi 6122 | 
. . . . 5
⊢  Nc ℘1A ∈ NC | 
| 20 |   | cenc.2 | 
. . . . . . 7
⊢ B ∈
V | 
| 21 | 20 | pw1ex 4304 | 
. . . . . 6
⊢ ℘1B ∈
V | 
| 22 | 21 | ncelncsi 6122 | 
. . . . 5
⊢  Nc ℘1B ∈ NC | 
| 23 |   | elce 6176 | 
. . . . 5
⊢ (( Nc ℘1A ∈ NC ∧ Nc ℘1B ∈ NC ) → (g ∈ ( Nc ℘1A ↑c Nc ℘1B) ↔ ∃p∃t(℘1p ∈ Nc ℘1A ∧ ℘1t ∈ Nc ℘1B ∧ g ≈ (p
↑m t)))) | 
| 24 | 19, 22, 23 | mp2an 653 | 
. . . 4
⊢ (g ∈ ( Nc ℘1A ↑c Nc ℘1B) ↔ ∃p∃t(℘1p ∈ Nc ℘1A ∧ ℘1t ∈ Nc ℘1B ∧ g ≈ (p
↑m t))) | 
| 25 |   | elnc 6126 | 
. . . 4
⊢ (g ∈ Nc (A
↑m B) ↔
g ≈ (A ↑m B)) | 
| 26 | 16, 24, 25 | 3imtr4i 257 | 
. . 3
⊢ (g ∈ ( Nc ℘1A ↑c Nc ℘1B) → g
∈ Nc (A ↑m B)) | 
| 27 | 26 | ssriv 3278 | 
. 2
⊢ ( Nc ℘1A ↑c Nc ℘1B) ⊆ Nc (A
↑m B) | 
| 28 | 18 | ncid 6124 | 
. . . . 5
⊢ ℘1A ∈ Nc ℘1A | 
| 29 | 21 | ncid 6124 | 
. . . . 5
⊢ ℘1B ∈ Nc ℘1B | 
| 30 |   | pw1eq 4144 | 
. . . . . . . . 9
⊢ (a = A →
℘1a = ℘1A) | 
| 31 | 30 | eleq1d 2419 | 
. . . . . . . 8
⊢ (a = A →
(℘1a ∈ Nc ℘1A ↔ ℘1A ∈ Nc ℘1A)) | 
| 32 | 31 | adantr 451 | 
. . . . . . 7
⊢ ((a = A ∧ b = B) → (℘1a ∈ Nc ℘1A ↔ ℘1A ∈ Nc ℘1A)) | 
| 33 |   | pw1eq 4144 | 
. . . . . . . . 9
⊢ (b = B →
℘1b = ℘1B) | 
| 34 | 33 | eleq1d 2419 | 
. . . . . . . 8
⊢ (b = B →
(℘1b ∈ Nc ℘1B ↔ ℘1B ∈ Nc ℘1B)) | 
| 35 | 34 | adantl 452 | 
. . . . . . 7
⊢ ((a = A ∧ b = B) → (℘1b ∈ Nc ℘1B ↔ ℘1B ∈ Nc ℘1B)) | 
| 36 |   | oveq12 5533 | 
. . . . . . . 8
⊢ ((a = A ∧ b = B) → (a
↑m b) = (A ↑m B)) | 
| 37 | 36 | breq2d 4652 | 
. . . . . . 7
⊢ ((a = A ∧ b = B) → (g
≈ (a ↑m
b) ↔ g ≈ (A
↑m B))) | 
| 38 | 32, 35, 37 | 3anbi123d 1252 | 
. . . . . 6
⊢ ((a = A ∧ b = B) → ((℘1a ∈ Nc ℘1A ∧ ℘1b ∈ Nc ℘1B ∧ g ≈ (a
↑m b)) ↔ (℘1A ∈ Nc ℘1A ∧ ℘1B ∈ Nc ℘1B ∧ g ≈ (A
↑m B)))) | 
| 39 | 17, 20, 38 | spc2ev 2948 | 
. . . . 5
⊢ ((℘1A ∈ Nc ℘1A ∧ ℘1B ∈ Nc ℘1B ∧ g ≈ (A
↑m B)) → ∃a∃b(℘1a ∈ Nc ℘1A ∧ ℘1b ∈ Nc ℘1B ∧ g ≈ (a
↑m b))) | 
| 40 | 28, 29, 39 | mp3an12 1267 | 
. . . 4
⊢ (g ≈ (A
↑m B) → ∃a∃b(℘1a ∈ Nc ℘1A ∧ ℘1b ∈ Nc ℘1B ∧ g ≈ (a
↑m b))) | 
| 41 |   | elce 6176 | 
. . . . 5
⊢ (( Nc ℘1A ∈ NC ∧ Nc ℘1B ∈ NC ) → (g ∈ ( Nc ℘1A ↑c Nc ℘1B) ↔ ∃a∃b(℘1a ∈ Nc ℘1A ∧ ℘1b ∈ Nc ℘1B ∧ g ≈ (a
↑m b)))) | 
| 42 | 19, 22, 41 | mp2an 653 | 
. . . 4
⊢ (g ∈ ( Nc ℘1A ↑c Nc ℘1B) ↔ ∃a∃b(℘1a ∈ Nc ℘1A ∧ ℘1b ∈ Nc ℘1B ∧ g ≈ (a
↑m b))) | 
| 43 | 40, 25, 42 | 3imtr4i 257 | 
. . 3
⊢ (g ∈ Nc (A
↑m B) →
g ∈ (
Nc ℘1A ↑c Nc ℘1B)) | 
| 44 | 43 | ssriv 3278 | 
. 2
⊢  Nc (A
↑m B) ⊆ ( Nc ℘1A ↑c Nc ℘1B) | 
| 45 | 27, 44 | eqssi 3289 | 
1
⊢ ( Nc ℘1A ↑c Nc ℘1B) = Nc (A ↑m B) |