Proof of Theorem phplem2OLD
| Step | Hyp | Ref
| Expression |
| 1 | | snex 5416 |
. . . . . 6
⊢
{〈𝐵, 𝐴〉} ∈
V |
| 2 | | phplem2OLD.2 |
. . . . . . 7
⊢ 𝐵 ∈ V |
| 3 | | phplem2OLD.1 |
. . . . . . 7
⊢ 𝐴 ∈ V |
| 4 | 2, 3 | f1osn 6868 |
. . . . . 6
⊢
{〈𝐵, 𝐴〉}:{𝐵}–1-1-onto→{𝐴} |
| 5 | | f1oen3g 8989 |
. . . . . 6
⊢
(({〈𝐵, 𝐴〉} ∈ V ∧
{〈𝐵, 𝐴〉}:{𝐵}–1-1-onto→{𝐴}) → {𝐵} ≈ {𝐴}) |
| 6 | 1, 4, 5 | mp2an 692 |
. . . . 5
⊢ {𝐵} ≈ {𝐴} |
| 7 | 3 | difexi 5310 |
. . . . . 6
⊢ (𝐴 ∖ {𝐵}) ∈ V |
| 8 | 7 | enref 9007 |
. . . . 5
⊢ (𝐴 ∖ {𝐵}) ≈ (𝐴 ∖ {𝐵}) |
| 9 | 6, 8 | pm3.2i 470 |
. . . 4
⊢ ({𝐵} ≈ {𝐴} ∧ (𝐴 ∖ {𝐵}) ≈ (𝐴 ∖ {𝐵})) |
| 10 | | incom 4189 |
. . . . . 6
⊢ ({𝐴} ∩ (𝐴 ∖ {𝐵})) = ((𝐴 ∖ {𝐵}) ∩ {𝐴}) |
| 11 | | difss 4116 |
. . . . . . . . 9
⊢ (𝐴 ∖ {𝐵}) ⊆ 𝐴 |
| 12 | | ssrin 4222 |
. . . . . . . . 9
⊢ ((𝐴 ∖ {𝐵}) ⊆ 𝐴 → ((𝐴 ∖ {𝐵}) ∩ {𝐴}) ⊆ (𝐴 ∩ {𝐴})) |
| 13 | 11, 12 | ax-mp 5 |
. . . . . . . 8
⊢ ((𝐴 ∖ {𝐵}) ∩ {𝐴}) ⊆ (𝐴 ∩ {𝐴}) |
| 14 | | nnord 7877 |
. . . . . . . . 9
⊢ (𝐴 ∈ ω → Ord 𝐴) |
| 15 | | orddisj 6401 |
. . . . . . . . 9
⊢ (Ord
𝐴 → (𝐴 ∩ {𝐴}) = ∅) |
| 16 | 14, 15 | syl 17 |
. . . . . . . 8
⊢ (𝐴 ∈ ω → (𝐴 ∩ {𝐴}) = ∅) |
| 17 | 13, 16 | sseqtrid 4006 |
. . . . . . 7
⊢ (𝐴 ∈ ω → ((𝐴 ∖ {𝐵}) ∩ {𝐴}) ⊆ ∅) |
| 18 | | ss0 4382 |
. . . . . . 7
⊢ (((𝐴 ∖ {𝐵}) ∩ {𝐴}) ⊆ ∅ → ((𝐴 ∖ {𝐵}) ∩ {𝐴}) = ∅) |
| 19 | 17, 18 | syl 17 |
. . . . . 6
⊢ (𝐴 ∈ ω → ((𝐴 ∖ {𝐵}) ∩ {𝐴}) = ∅) |
| 20 | 10, 19 | eqtrid 2781 |
. . . . 5
⊢ (𝐴 ∈ ω → ({𝐴} ∩ (𝐴 ∖ {𝐵})) = ∅) |
| 21 | | disjdif 4452 |
. . . . 5
⊢ ({𝐵} ∩ (𝐴 ∖ {𝐵})) = ∅ |
| 22 | 20, 21 | jctil 519 |
. . . 4
⊢ (𝐴 ∈ ω → (({𝐵} ∩ (𝐴 ∖ {𝐵})) = ∅ ∧ ({𝐴} ∩ (𝐴 ∖ {𝐵})) = ∅)) |
| 23 | | unen 9068 |
. . . 4
⊢ ((({𝐵} ≈ {𝐴} ∧ (𝐴 ∖ {𝐵}) ≈ (𝐴 ∖ {𝐵})) ∧ (({𝐵} ∩ (𝐴 ∖ {𝐵})) = ∅ ∧ ({𝐴} ∩ (𝐴 ∖ {𝐵})) = ∅)) → ({𝐵} ∪ (𝐴 ∖ {𝐵})) ≈ ({𝐴} ∪ (𝐴 ∖ {𝐵}))) |
| 24 | 9, 22, 23 | sylancr 587 |
. . 3
⊢ (𝐴 ∈ ω → ({𝐵} ∪ (𝐴 ∖ {𝐵})) ≈ ({𝐴} ∪ (𝐴 ∖ {𝐵}))) |
| 25 | 24 | adantr 480 |
. 2
⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ 𝐴) → ({𝐵} ∪ (𝐴 ∖ {𝐵})) ≈ ({𝐴} ∪ (𝐴 ∖ {𝐵}))) |
| 26 | | uncom 4138 |
. . . 4
⊢ ({𝐵} ∪ (𝐴 ∖ {𝐵})) = ((𝐴 ∖ {𝐵}) ∪ {𝐵}) |
| 27 | | difsnid 4790 |
. . . 4
⊢ (𝐵 ∈ 𝐴 → ((𝐴 ∖ {𝐵}) ∪ {𝐵}) = 𝐴) |
| 28 | 26, 27 | eqtrid 2781 |
. . 3
⊢ (𝐵 ∈ 𝐴 → ({𝐵} ∪ (𝐴 ∖ {𝐵})) = 𝐴) |
| 29 | 28 | adantl 481 |
. 2
⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ 𝐴) → ({𝐵} ∪ (𝐴 ∖ {𝐵})) = 𝐴) |
| 30 | | phplem1OLD 9236 |
. 2
⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ 𝐴) → ({𝐴} ∪ (𝐴 ∖ {𝐵})) = (suc 𝐴 ∖ {𝐵})) |
| 31 | 25, 29, 30 | 3brtr3d 5154 |
1
⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ 𝐴) → 𝐴 ≈ (suc 𝐴 ∖ {𝐵})) |