| Step | Hyp | Ref
| Expression |
| 1 | | n0 3560 |
. . 3
⊢ ((A +c 1c) ≠ ∅ ↔ ∃a a ∈ (A +c 1c)) |
| 2 | | peano2 4404 |
. . . . . . . 8
⊢ (A ∈ Nn → (A
+c 1c) ∈ Nn ) |
| 3 | | tfincl 4493 |
. . . . . . . 8
⊢ ((A +c 1c) ∈ Nn → Tfin (A
+c 1c) ∈ Nn ) |
| 4 | 2, 3 | syl 15 |
. . . . . . 7
⊢ (A ∈ Nn → Tfin
(A +c 1c) ∈ Nn
) |
| 5 | 4 | adantr 451 |
. . . . . 6
⊢ ((A ∈ Nn ∧ a ∈ (A +c 1c)) → Tfin (A
+c 1c) ∈ Nn ) |
| 6 | | tfincl 4493 |
. . . . . . . 8
⊢ (A ∈ Nn → Tfin
A ∈ Nn ) |
| 7 | | peano2 4404 |
. . . . . . . 8
⊢ ( Tfin A
∈ Nn → (
Tfin A +c 1c) ∈ Nn
) |
| 8 | 6, 7 | syl 15 |
. . . . . . 7
⊢ (A ∈ Nn → ( Tfin
A +c 1c) ∈ Nn
) |
| 9 | 8 | adantr 451 |
. . . . . 6
⊢ ((A ∈ Nn ∧ a ∈ (A +c 1c)) → ( Tfin A
+c 1c) ∈ Nn ) |
| 10 | | tfinpw1 4495 |
. . . . . . 7
⊢ (((A +c 1c) ∈ Nn ∧ a ∈ (A
+c 1c)) → 𝒫1a ∈ Tfin (A
+c 1c)) |
| 11 | 2, 10 | sylan 457 |
. . . . . 6
⊢ ((A ∈ Nn ∧ a ∈ (A +c 1c)) →
𝒫1a ∈ Tfin
(A +c
1c)) |
| 12 | | elsuc 4414 |
. . . . . . . 8
⊢ (a ∈ (A +c 1c) ↔ ∃b ∈ A ∃x ∈ ∼ ba = (b ∪ {x})) |
| 13 | | tfinpw1 4495 |
. . . . . . . . . . . 12
⊢ ((A ∈ Nn ∧ b ∈ A) → 𝒫1b ∈ Tfin A) |
| 14 | 13 | adantrr 697 |
. . . . . . . . . . 11
⊢ ((A ∈ Nn ∧ (b ∈ A ∧ x ∈ ∼ b)) → 𝒫1b ∈ Tfin A) |
| 15 | | vex 2863 |
. . . . . . . . . . . . . . 15
⊢ x ∈
V |
| 16 | 15 | elcompl 3226 |
. . . . . . . . . . . . . 14
⊢ (x ∈ ∼ b ↔ ¬ x
∈ b) |
| 17 | | snelpw1 4147 |
. . . . . . . . . . . . . 14
⊢ ({x} ∈
𝒫1b ↔ x ∈ b) |
| 18 | 16, 17 | xchbinxr 302 |
. . . . . . . . . . . . 13
⊢ (x ∈ ∼ b ↔ ¬ {x} ∈
𝒫1b) |
| 19 | 18 | biimpi 186 |
. . . . . . . . . . . 12
⊢ (x ∈ ∼ b → ¬ {x} ∈
𝒫1b) |
| 20 | 19 | ad2antll 709 |
. . . . . . . . . . 11
⊢ ((A ∈ Nn ∧ (b ∈ A ∧ x ∈ ∼ b)) → ¬ {x} ∈
𝒫1b) |
| 21 | | snex 4112 |
. . . . . . . . . . . 12
⊢ {x} ∈
V |
| 22 | 21 | elsuci 4415 |
. . . . . . . . . . 11
⊢
((𝒫1b ∈ Tfin
A ∧ ¬
{x} ∈
𝒫1b) →
(𝒫1b ∪ {{x}}) ∈ ( Tfin A
+c 1c)) |
| 23 | 14, 20, 22 | syl2anc 642 |
. . . . . . . . . 10
⊢ ((A ∈ Nn ∧ (b ∈ A ∧ x ∈ ∼ b)) → (𝒫1b ∪ {{x}})
∈ ( Tfin A
+c 1c)) |
| 24 | | pw1eq 4144 |
. . . . . . . . . . . 12
⊢ (a = (b ∪
{x}) → 𝒫1a = 𝒫1(b ∪ {x})) |
| 25 | | pw1un 4164 |
. . . . . . . . . . . . 13
⊢
𝒫1(b ∪
{x}) = (𝒫1b ∪ 𝒫1{x}) |
| 26 | 15 | pw1sn 4166 |
. . . . . . . . . . . . . 14
⊢
𝒫1{x} =
{{x}} |
| 27 | 26 | uneq2i 3416 |
. . . . . . . . . . . . 13
⊢
(𝒫1b ∪
𝒫1{x}) =
(𝒫1b ∪ {{x}}) |
| 28 | 25, 27 | eqtri 2373 |
. . . . . . . . . . . 12
⊢
𝒫1(b ∪
{x}) = (𝒫1b ∪ {{x}}) |
| 29 | 24, 28 | syl6eq 2401 |
. . . . . . . . . . 11
⊢ (a = (b ∪
{x}) → 𝒫1a = (𝒫1b ∪ {{x}})) |
| 30 | 29 | eleq1d 2419 |
. . . . . . . . . 10
⊢ (a = (b ∪
{x}) → (𝒫1a ∈ ( Tfin A
+c 1c) ↔ (𝒫1b ∪ {{x}})
∈ ( Tfin A
+c 1c))) |
| 31 | 23, 30 | syl5ibrcom 213 |
. . . . . . . . 9
⊢ ((A ∈ Nn ∧ (b ∈ A ∧ x ∈ ∼ b)) → (a =
(b ∪ {x}) → 𝒫1a ∈ ( Tfin A
+c 1c))) |
| 32 | 31 | rexlimdvva 2746 |
. . . . . . . 8
⊢ (A ∈ Nn → (∃b ∈ A ∃x ∈ ∼ ba = (b ∪ {x})
→ 𝒫1a ∈ ( Tfin
A +c
1c))) |
| 33 | 12, 32 | syl5bi 208 |
. . . . . . 7
⊢ (A ∈ Nn → (a ∈ (A
+c 1c) → 𝒫1a ∈ ( Tfin A
+c 1c))) |
| 34 | 33 | imp 418 |
. . . . . 6
⊢ ((A ∈ Nn ∧ a ∈ (A +c 1c)) →
𝒫1a ∈ ( Tfin
A +c
1c)) |
| 35 | | nnceleq 4431 |
. . . . . 6
⊢ ((( Tfin (A
+c 1c) ∈ Nn ∧ ( Tfin A
+c 1c) ∈ Nn ) ∧
(𝒫1a ∈ Tfin
(A +c 1c) ∧ 𝒫1a ∈ ( Tfin A
+c 1c))) → Tfin (A
+c 1c) = ( Tfin
A +c
1c)) |
| 36 | 5, 9, 11, 34, 35 | syl22anc 1183 |
. . . . 5
⊢ ((A ∈ Nn ∧ a ∈ (A +c 1c)) → Tfin (A
+c 1c) = ( Tfin
A +c
1c)) |
| 37 | 36 | ex 423 |
. . . 4
⊢ (A ∈ Nn → (a ∈ (A
+c 1c) → Tfin (A
+c 1c) = ( Tfin
A +c
1c))) |
| 38 | 37 | exlimdv 1636 |
. . 3
⊢ (A ∈ Nn → (∃a a ∈ (A
+c 1c) → Tfin (A
+c 1c) = ( Tfin
A +c
1c))) |
| 39 | 1, 38 | syl5bi 208 |
. 2
⊢ (A ∈ Nn → ((A
+c 1c) ≠ ∅ →
Tfin (A +c 1c) = ( Tfin A
+c 1c))) |
| 40 | 39 | imp 418 |
1
⊢ ((A ∈ Nn ∧ (A +c 1c) ≠ ∅) → Tfin (A
+c 1c) = ( Tfin
A +c
1c)) |