| Step | Hyp | Ref
 | Expression | 
| 1 |   | tfrfun 6378 | 
. . . 4
⊢ Fun
recs(𝐺) | 
| 2 |   | tfri1dALT.1 | 
. . . . 5
⊢ 𝐹 = recs(𝐺) | 
| 3 | 2 | funeqi 5279 | 
. . . 4
⊢ (Fun
𝐹 ↔ Fun recs(𝐺)) | 
| 4 | 1, 3 | mpbir 146 | 
. . 3
⊢ Fun 𝐹 | 
| 5 | 4 | a1i 9 | 
. 2
⊢ (𝜑 → Fun 𝐹) | 
| 6 |   | eqid 2196 | 
. . . . . 6
⊢ {𝑎 ∣ ∃𝑏 ∈ On (𝑎 Fn 𝑏 ∧ ∀𝑐 ∈ 𝑏 (𝑎‘𝑐) = (𝐺‘(𝑎 ↾ 𝑐)))} = {𝑎 ∣ ∃𝑏 ∈ On (𝑎 Fn 𝑏 ∧ ∀𝑐 ∈ 𝑏 (𝑎‘𝑐) = (𝐺‘(𝑎 ↾ 𝑐)))} | 
| 7 | 6 | tfrlem8 6376 | 
. . . . 5
⊢ Ord dom
recs(𝐺) | 
| 8 | 2 | dmeqi 4867 | 
. . . . . 6
⊢ dom 𝐹 = dom recs(𝐺) | 
| 9 |   | ordeq 4407 | 
. . . . . 6
⊢ (dom
𝐹 = dom recs(𝐺) → (Ord dom 𝐹 ↔ Ord dom recs(𝐺))) | 
| 10 | 8, 9 | ax-mp 5 | 
. . . . 5
⊢ (Ord dom
𝐹 ↔ Ord dom recs(𝐺)) | 
| 11 | 7, 10 | mpbir 146 | 
. . . 4
⊢ Ord dom
𝐹 | 
| 12 |   | ordsson 4528 | 
. . . 4
⊢ (Ord dom
𝐹 → dom 𝐹 ⊆ On) | 
| 13 | 11, 12 | mp1i 10 | 
. . 3
⊢ (𝜑 → dom 𝐹 ⊆ On) | 
| 14 |   | tfri1dALT.2 | 
. . . . . . . . . 10
⊢ (𝜑 → ∀𝑥(Fun 𝐺 ∧ (𝐺‘𝑥) ∈ V)) | 
| 15 |   | simpl 109 | 
. . . . . . . . . . 11
⊢ ((Fun
𝐺 ∧ (𝐺‘𝑥) ∈ V) → Fun 𝐺) | 
| 16 | 15 | alimi 1469 | 
. . . . . . . . . 10
⊢
(∀𝑥(Fun 𝐺 ∧ (𝐺‘𝑥) ∈ V) → ∀𝑥Fun 𝐺) | 
| 17 | 14, 16 | syl 14 | 
. . . . . . . . 9
⊢ (𝜑 → ∀𝑥Fun 𝐺) | 
| 18 | 17 | 19.21bi 1572 | 
. . . . . . . 8
⊢ (𝜑 → Fun 𝐺) | 
| 19 | 18 | adantr 276 | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑧 ∈ On) → Fun 𝐺) | 
| 20 |   | ordon 4522 | 
. . . . . . . 8
⊢ Ord
On | 
| 21 | 20 | a1i 9 | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑧 ∈ On) → Ord On) | 
| 22 |   | simpr 110 | 
. . . . . . . . . . 11
⊢ ((Fun
𝐺 ∧ (𝐺‘𝑥) ∈ V) → (𝐺‘𝑥) ∈ V) | 
| 23 | 22 | alimi 1469 | 
. . . . . . . . . 10
⊢
(∀𝑥(Fun 𝐺 ∧ (𝐺‘𝑥) ∈ V) → ∀𝑥(𝐺‘𝑥) ∈ V) | 
| 24 |   | fveq2 5558 | 
. . . . . . . . . . . 12
⊢ (𝑥 = 𝑓 → (𝐺‘𝑥) = (𝐺‘𝑓)) | 
| 25 | 24 | eleq1d 2265 | 
. . . . . . . . . . 11
⊢ (𝑥 = 𝑓 → ((𝐺‘𝑥) ∈ V ↔ (𝐺‘𝑓) ∈ V)) | 
| 26 | 25 | spv 1874 | 
. . . . . . . . . 10
⊢
(∀𝑥(𝐺‘𝑥) ∈ V → (𝐺‘𝑓) ∈ V) | 
| 27 | 14, 23, 26 | 3syl 17 | 
. . . . . . . . 9
⊢ (𝜑 → (𝐺‘𝑓) ∈ V) | 
| 28 | 27 | adantr 276 | 
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑧 ∈ On) → (𝐺‘𝑓) ∈ V) | 
| 29 | 28 | 3ad2ant1 1020 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑧 ∈ On) ∧ 𝑦 ∈ On ∧ 𝑓 Fn 𝑦) → (𝐺‘𝑓) ∈ V) | 
| 30 |   | onsuc 4537 | 
. . . . . . . . 9
⊢ (𝑦 ∈ On → suc 𝑦 ∈ On) | 
| 31 |   | unon 4547 | 
. . . . . . . . 9
⊢ ∪ On = On | 
| 32 | 30, 31 | eleq2s 2291 | 
. . . . . . . 8
⊢ (𝑦 ∈ ∪ On → suc 𝑦 ∈ On) | 
| 33 | 32 | adantl 277 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑧 ∈ On) ∧ 𝑦 ∈ ∪ On)
→ suc 𝑦 ∈
On) | 
| 34 |   | onsuc 4537 | 
. . . . . . . 8
⊢ (𝑧 ∈ On → suc 𝑧 ∈ On) | 
| 35 | 34 | adantl 277 | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑧 ∈ On) → suc 𝑧 ∈ On) | 
| 36 | 2, 19, 21, 29, 33, 35 | tfr1on 6408 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑧 ∈ On) → suc 𝑧 ⊆ dom 𝐹) | 
| 37 |   | vex 2766 | 
. . . . . . 7
⊢ 𝑧 ∈ V | 
| 38 | 37 | sucid 4452 | 
. . . . . 6
⊢ 𝑧 ∈ suc 𝑧 | 
| 39 |   | ssel2 3178 | 
. . . . . 6
⊢ ((suc
𝑧 ⊆ dom 𝐹 ∧ 𝑧 ∈ suc 𝑧) → 𝑧 ∈ dom 𝐹) | 
| 40 | 36, 38, 39 | sylancl 413 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑧 ∈ On) → 𝑧 ∈ dom 𝐹) | 
| 41 | 40 | ex 115 | 
. . . 4
⊢ (𝜑 → (𝑧 ∈ On → 𝑧 ∈ dom 𝐹)) | 
| 42 | 41 | ssrdv 3189 | 
. . 3
⊢ (𝜑 → On ⊆ dom 𝐹) | 
| 43 | 13, 42 | eqssd 3200 | 
. 2
⊢ (𝜑 → dom 𝐹 = On) | 
| 44 |   | df-fn 5261 | 
. 2
⊢ (𝐹 Fn On ↔ (Fun 𝐹 ∧ dom 𝐹 = On)) | 
| 45 | 5, 43, 44 | sylanbrc 417 | 
1
⊢ (𝜑 → 𝐹 Fn On) |