| Step | Hyp | Ref
| Expression |
| 1 | | dftr2 5261 |
. . 3
⊢ (Tr suc
𝐴 ↔ ∀𝑧∀𝑦((𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) → 𝑧 ∈ suc 𝐴)) |
| 2 | | sssucid 6464 |
. . . . . . . 8
⊢ 𝐴 ⊆ suc 𝐴 |
| 3 | | idn1 44594 |
. . . . . . . . 9
⊢ ( Tr 𝐴 ▶ Tr 𝐴 ) |
| 4 | | idn2 44633 |
. . . . . . . . . 10
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) ▶ (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) ) |
| 5 | | simpl 482 |
. . . . . . . . . 10
⊢ ((𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) → 𝑧 ∈ 𝑦) |
| 6 | 4, 5 | e2 44651 |
. . . . . . . . 9
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) ▶ 𝑧 ∈ 𝑦 ) |
| 7 | | idn3 44635 |
. . . . . . . . 9
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) , 𝑦 ∈ 𝐴 ▶ 𝑦 ∈ 𝐴 ) |
| 8 | | trel 5268 |
. . . . . . . . . 10
⊢ (Tr 𝐴 → ((𝑧 ∈ 𝑦 ∧ 𝑦 ∈ 𝐴) → 𝑧 ∈ 𝐴)) |
| 9 | 8 | expd 415 |
. . . . . . . . 9
⊢ (Tr 𝐴 → (𝑧 ∈ 𝑦 → (𝑦 ∈ 𝐴 → 𝑧 ∈ 𝐴))) |
| 10 | 3, 6, 7, 9 | e123 44782 |
. . . . . . . 8
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) , 𝑦 ∈ 𝐴 ▶ 𝑧 ∈ 𝐴 ) |
| 11 | | ssel 3977 |
. . . . . . . 8
⊢ (𝐴 ⊆ suc 𝐴 → (𝑧 ∈ 𝐴 → 𝑧 ∈ suc 𝐴)) |
| 12 | 2, 10, 11 | e03 44760 |
. . . . . . 7
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) , 𝑦 ∈ 𝐴 ▶ 𝑧 ∈ suc 𝐴 ) |
| 13 | 12 | in3 44629 |
. . . . . 6
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) ▶ (𝑦 ∈ 𝐴 → 𝑧 ∈ suc 𝐴) ) |
| 14 | | idn3 44635 |
. . . . . . . . 9
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) , 𝑦 = 𝐴 ▶ 𝑦 = 𝐴 ) |
| 15 | | eleq2 2830 |
. . . . . . . . . 10
⊢ (𝑦 = 𝐴 → (𝑧 ∈ 𝑦 ↔ 𝑧 ∈ 𝐴)) |
| 16 | 15 | biimpcd 249 |
. . . . . . . . 9
⊢ (𝑧 ∈ 𝑦 → (𝑦 = 𝐴 → 𝑧 ∈ 𝐴)) |
| 17 | 6, 14, 16 | e23 44775 |
. . . . . . . 8
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) , 𝑦 = 𝐴 ▶ 𝑧 ∈ 𝐴 ) |
| 18 | 2, 17, 11 | e03 44760 |
. . . . . . 7
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) , 𝑦 = 𝐴 ▶ 𝑧 ∈ suc 𝐴 ) |
| 19 | 18 | in3 44629 |
. . . . . 6
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) ▶ (𝑦 = 𝐴 → 𝑧 ∈ suc 𝐴) ) |
| 20 | | simpr 484 |
. . . . . . . 8
⊢ ((𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) → 𝑦 ∈ suc 𝐴) |
| 21 | 4, 20 | e2 44651 |
. . . . . . 7
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) ▶ 𝑦 ∈ suc 𝐴 ) |
| 22 | | elsuci 6451 |
. . . . . . 7
⊢ (𝑦 ∈ suc 𝐴 → (𝑦 ∈ 𝐴 ∨ 𝑦 = 𝐴)) |
| 23 | 21, 22 | e2 44651 |
. . . . . 6
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) ▶ (𝑦 ∈ 𝐴 ∨ 𝑦 = 𝐴) ) |
| 24 | | jao 963 |
. . . . . 6
⊢ ((𝑦 ∈ 𝐴 → 𝑧 ∈ suc 𝐴) → ((𝑦 = 𝐴 → 𝑧 ∈ suc 𝐴) → ((𝑦 ∈ 𝐴 ∨ 𝑦 = 𝐴) → 𝑧 ∈ suc 𝐴))) |
| 25 | 13, 19, 23, 24 | e222 44656 |
. . . . 5
⊢ ( Tr 𝐴 , (𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) ▶ 𝑧 ∈ suc 𝐴 ) |
| 26 | 25 | in2 44625 |
. . . 4
⊢ ( Tr 𝐴 ▶ ((𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) → 𝑧 ∈ suc 𝐴) ) |
| 27 | 26 | gen12 44638 |
. . 3
⊢ ( Tr 𝐴 ▶ ∀𝑧∀𝑦((𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) → 𝑧 ∈ suc 𝐴) ) |
| 28 | | biimpr 220 |
. . 3
⊢ ((Tr suc
𝐴 ↔ ∀𝑧∀𝑦((𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) → 𝑧 ∈ suc 𝐴)) → (∀𝑧∀𝑦((𝑧 ∈ 𝑦 ∧ 𝑦 ∈ suc 𝐴) → 𝑧 ∈ suc 𝐴) → Tr suc 𝐴)) |
| 29 | 1, 27, 28 | e01 44711 |
. 2
⊢ ( Tr 𝐴 ▶ Tr suc
𝐴 ) |
| 30 | 29 | in1 44591 |
1
⊢ (Tr 𝐴 → Tr suc 𝐴) |