Proof of Theorem bnj1123
| Step | Hyp | Ref
| Expression |
| 1 | | bnj1123.2 |
. 2
⊢ (𝜂′ ↔ [𝑗 / 𝑖]𝜂) |
| 2 | | bnj1123.1 |
. . 3
⊢ (𝜂 ↔ ((𝑓 ∈ 𝐾 ∧ 𝑖 ∈ dom 𝑓) → (𝑓‘𝑖) ⊆ 𝐵)) |
| 3 | 2 | sbcbii 3491 |
. 2
⊢
([𝑗 / 𝑖]𝜂 ↔ [𝑗 / 𝑖]((𝑓 ∈ 𝐾 ∧ 𝑖 ∈ dom 𝑓) → (𝑓‘𝑖) ⊆ 𝐵)) |
| 4 | | vex 3203 |
. . 3
⊢ 𝑗 ∈ V |
| 5 | | bnj1123.3 |
. . . . . . . 8
⊢ 𝐾 = {𝑓 ∣ ∃𝑛 ∈ 𝐷 (𝑓 Fn 𝑛 ∧ 𝜑 ∧ 𝜓)} |
| 6 | | nfcv 2764 |
. . . . . . . . . 10
⊢
Ⅎ𝑖𝐷 |
| 7 | | nfv 1843 |
. . . . . . . . . . 11
⊢
Ⅎ𝑖 𝑓 Fn 𝑛 |
| 8 | | nfv 1843 |
. . . . . . . . . . 11
⊢
Ⅎ𝑖𝜑 |
| 9 | | bnj1123.4 |
. . . . . . . . . . . . 13
⊢ (𝜓 ↔ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅))) |
| 10 | 9 | bnj1095 30852 |
. . . . . . . . . . . 12
⊢ (𝜓 → ∀𝑖𝜓) |
| 11 | 10 | nf5i 2024 |
. . . . . . . . . . 11
⊢
Ⅎ𝑖𝜓 |
| 12 | 7, 8, 11 | nf3an 1831 |
. . . . . . . . . 10
⊢
Ⅎ𝑖(𝑓 Fn 𝑛 ∧ 𝜑 ∧ 𝜓) |
| 13 | 6, 12 | nfrex 3007 |
. . . . . . . . 9
⊢
Ⅎ𝑖∃𝑛 ∈ 𝐷 (𝑓 Fn 𝑛 ∧ 𝜑 ∧ 𝜓) |
| 14 | 13 | nfab 2769 |
. . . . . . . 8
⊢
Ⅎ𝑖{𝑓 ∣ ∃𝑛 ∈ 𝐷 (𝑓 Fn 𝑛 ∧ 𝜑 ∧ 𝜓)} |
| 15 | 5, 14 | nfcxfr 2762 |
. . . . . . 7
⊢
Ⅎ𝑖𝐾 |
| 16 | 15 | nfcri 2758 |
. . . . . 6
⊢
Ⅎ𝑖 𝑓 ∈ 𝐾 |
| 17 | | nfv 1843 |
. . . . . 6
⊢
Ⅎ𝑖 𝑗 ∈ dom 𝑓 |
| 18 | 16, 17 | nfan 1828 |
. . . . 5
⊢
Ⅎ𝑖(𝑓 ∈ 𝐾 ∧ 𝑗 ∈ dom 𝑓) |
| 19 | | nfv 1843 |
. . . . 5
⊢
Ⅎ𝑖(𝑓‘𝑗) ⊆ 𝐵 |
| 20 | 18, 19 | nfim 1825 |
. . . 4
⊢
Ⅎ𝑖((𝑓 ∈ 𝐾 ∧ 𝑗 ∈ dom 𝑓) → (𝑓‘𝑗) ⊆ 𝐵) |
| 21 | | eleq1 2689 |
. . . . . 6
⊢ (𝑖 = 𝑗 → (𝑖 ∈ dom 𝑓 ↔ 𝑗 ∈ dom 𝑓)) |
| 22 | 21 | anbi2d 740 |
. . . . 5
⊢ (𝑖 = 𝑗 → ((𝑓 ∈ 𝐾 ∧ 𝑖 ∈ dom 𝑓) ↔ (𝑓 ∈ 𝐾 ∧ 𝑗 ∈ dom 𝑓))) |
| 23 | | fveq2 6191 |
. . . . . 6
⊢ (𝑖 = 𝑗 → (𝑓‘𝑖) = (𝑓‘𝑗)) |
| 24 | 23 | sseq1d 3632 |
. . . . 5
⊢ (𝑖 = 𝑗 → ((𝑓‘𝑖) ⊆ 𝐵 ↔ (𝑓‘𝑗) ⊆ 𝐵)) |
| 25 | 22, 24 | imbi12d 334 |
. . . 4
⊢ (𝑖 = 𝑗 → (((𝑓 ∈ 𝐾 ∧ 𝑖 ∈ dom 𝑓) → (𝑓‘𝑖) ⊆ 𝐵) ↔ ((𝑓 ∈ 𝐾 ∧ 𝑗 ∈ dom 𝑓) → (𝑓‘𝑗) ⊆ 𝐵))) |
| 26 | 20, 25 | sbciegf 3467 |
. . 3
⊢ (𝑗 ∈ V → ([𝑗 / 𝑖]((𝑓 ∈ 𝐾 ∧ 𝑖 ∈ dom 𝑓) → (𝑓‘𝑖) ⊆ 𝐵) ↔ ((𝑓 ∈ 𝐾 ∧ 𝑗 ∈ dom 𝑓) → (𝑓‘𝑗) ⊆ 𝐵))) |
| 27 | 4, 26 | ax-mp 5 |
. 2
⊢
([𝑗 / 𝑖]((𝑓 ∈ 𝐾 ∧ 𝑖 ∈ dom 𝑓) → (𝑓‘𝑖) ⊆ 𝐵) ↔ ((𝑓 ∈ 𝐾 ∧ 𝑗 ∈ dom 𝑓) → (𝑓‘𝑗) ⊆ 𝐵)) |
| 28 | 1, 3, 27 | 3bitri 286 |
1
⊢ (𝜂′ ↔ ((𝑓 ∈ 𝐾 ∧ 𝑗 ∈ dom 𝑓) → (𝑓‘𝑗) ⊆ 𝐵)) |