| Step | Hyp | Ref
 | Expression | 
| 1 |   | 0lt2o 6499 | 
. . . . . 6
⊢ ∅
∈ 2o | 
| 2 | 1 | a1i 9 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑖 ∈ ω) → ∅ ∈
2o) | 
| 3 |   | 1lt2o 6500 | 
. . . . . 6
⊢
1o ∈ 2o | 
| 4 | 3 | a1i 9 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑖 ∈ ω) → 1o ∈
2o) | 
| 5 |   | peano2 4631 | 
. . . . . . . 8
⊢ (𝑖 ∈ ω → suc 𝑖 ∈
ω) | 
| 6 | 5 | adantl 277 | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑖 ∈ ω) → suc 𝑖 ∈
ω) | 
| 7 |   | nnfi 6933 | 
. . . . . . 7
⊢ (suc
𝑖 ∈ ω → suc
𝑖 ∈
Fin) | 
| 8 | 6, 7 | syl 14 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑖 ∈ ω) → suc 𝑖 ∈ Fin) | 
| 9 |   | 2ssom 6582 | 
. . . . . . . . 9
⊢
2o ⊆ ω | 
| 10 |   | nninfwlpoimlemg.f | 
. . . . . . . . . . 11
⊢ (𝜑 → 𝐹:ω⟶2o) | 
| 11 | 10 | ad2antrr 488 | 
. . . . . . . . . 10
⊢ (((𝜑 ∧ 𝑖 ∈ ω) ∧ 𝑥 ∈ suc 𝑖) → 𝐹:ω⟶2o) | 
| 12 |   | simpr 110 | 
. . . . . . . . . . 11
⊢ (((𝜑 ∧ 𝑖 ∈ ω) ∧ 𝑥 ∈ suc 𝑖) → 𝑥 ∈ suc 𝑖) | 
| 13 | 6 | adantr 276 | 
. . . . . . . . . . 11
⊢ (((𝜑 ∧ 𝑖 ∈ ω) ∧ 𝑥 ∈ suc 𝑖) → suc 𝑖 ∈ ω) | 
| 14 |   | elnn 4642 | 
. . . . . . . . . . 11
⊢ ((𝑥 ∈ suc 𝑖 ∧ suc 𝑖 ∈ ω) → 𝑥 ∈ ω) | 
| 15 | 12, 13, 14 | syl2anc 411 | 
. . . . . . . . . 10
⊢ (((𝜑 ∧ 𝑖 ∈ ω) ∧ 𝑥 ∈ suc 𝑖) → 𝑥 ∈ ω) | 
| 16 | 11, 15 | ffvelcdmd 5698 | 
. . . . . . . . 9
⊢ (((𝜑 ∧ 𝑖 ∈ ω) ∧ 𝑥 ∈ suc 𝑖) → (𝐹‘𝑥) ∈ 2o) | 
| 17 | 9, 16 | sselid 3181 | 
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑖 ∈ ω) ∧ 𝑥 ∈ suc 𝑖) → (𝐹‘𝑥) ∈ ω) | 
| 18 |   | peano1 4630 | 
. . . . . . . . 9
⊢ ∅
∈ ω | 
| 19 | 18 | a1i 9 | 
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑖 ∈ ω) ∧ 𝑥 ∈ suc 𝑖) → ∅ ∈
ω) | 
| 20 |   | nndceq 6557 | 
. . . . . . . 8
⊢ (((𝐹‘𝑥) ∈ ω ∧ ∅ ∈
ω) → DECID (𝐹‘𝑥) = ∅) | 
| 21 | 17, 19, 20 | syl2anc 411 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑖 ∈ ω) ∧ 𝑥 ∈ suc 𝑖) → DECID (𝐹‘𝑥) = ∅) | 
| 22 | 21 | ralrimiva 2570 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑖 ∈ ω) → ∀𝑥 ∈ suc 𝑖DECID (𝐹‘𝑥) = ∅) | 
| 23 |   | finexdc 6963 | 
. . . . . 6
⊢ ((suc
𝑖 ∈ Fin ∧
∀𝑥 ∈ suc 𝑖DECID (𝐹‘𝑥) = ∅) → DECID
∃𝑥 ∈ suc 𝑖(𝐹‘𝑥) = ∅) | 
| 24 | 8, 22, 23 | syl2anc 411 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑖 ∈ ω) → DECID
∃𝑥 ∈ suc 𝑖(𝐹‘𝑥) = ∅) | 
| 25 | 2, 4, 24 | ifcldcd 3597 | 
. . . 4
⊢ ((𝜑 ∧ 𝑖 ∈ ω) → if(∃𝑥 ∈ suc 𝑖(𝐹‘𝑥) = ∅, ∅, 1o) ∈
2o) | 
| 26 |   | nninfwlpoimlemg.g | 
. . . 4
⊢ 𝐺 = (𝑖 ∈ ω ↦ if(∃𝑥 ∈ suc 𝑖(𝐹‘𝑥) = ∅, ∅,
1o)) | 
| 27 | 25, 26 | fmptd 5716 | 
. . 3
⊢ (𝜑 → 𝐺:ω⟶2o) | 
| 28 |   | 2onn 6579 | 
. . . . 5
⊢
2o ∈ ω | 
| 29 | 28 | elexi 2775 | 
. . . 4
⊢
2o ∈ V | 
| 30 |   | omex 4629 | 
. . . 4
⊢ ω
∈ V | 
| 31 | 29, 30 | elmap 6736 | 
. . 3
⊢ (𝐺 ∈ (2o
↑𝑚 ω) ↔ 𝐺:ω⟶2o) | 
| 32 | 27, 31 | sylibr 134 | 
. 2
⊢ (𝜑 → 𝐺 ∈ (2o
↑𝑚 ω)) | 
| 33 |   | simpr 110 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) | 
| 34 | 33 | iftrued 3568 | 
. . . . . 6
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → if(∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅, ∅, if(∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅, ∅, 1o)) =
∅) | 
| 35 |   | suceq 4437 | 
. . . . . . . . . . . 12
⊢ (𝑖 = suc 𝑗 → suc 𝑖 = suc suc 𝑗) | 
| 36 | 35 | rexeqdv 2700 | 
. . . . . . . . . . 11
⊢ (𝑖 = suc 𝑗 → (∃𝑥 ∈ suc 𝑖(𝐹‘𝑥) = ∅ ↔ ∃𝑥 ∈ suc suc 𝑗(𝐹‘𝑥) = ∅)) | 
| 37 | 36 | ifbid 3582 | 
. . . . . . . . . 10
⊢ (𝑖 = suc 𝑗 → if(∃𝑥 ∈ suc 𝑖(𝐹‘𝑥) = ∅, ∅, 1o) =
if(∃𝑥 ∈ suc suc
𝑗(𝐹‘𝑥) = ∅, ∅,
1o)) | 
| 38 |   | peano2 4631 | 
. . . . . . . . . . 11
⊢ (𝑗 ∈ ω → suc 𝑗 ∈
ω) | 
| 39 | 38 | adantl 277 | 
. . . . . . . . . 10
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → suc 𝑗 ∈
ω) | 
| 40 | 1 | a1i 9 | 
. . . . . . . . . . 11
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → ∅ ∈
2o) | 
| 41 | 3 | a1i 9 | 
. . . . . . . . . . 11
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → 1o ∈
2o) | 
| 42 |   | peano2 4631 | 
. . . . . . . . . . . . . 14
⊢ (suc
𝑗 ∈ ω → suc
suc 𝑗 ∈
ω) | 
| 43 | 39, 42 | syl 14 | 
. . . . . . . . . . . . 13
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → suc suc 𝑗 ∈
ω) | 
| 44 |   | nnfi 6933 | 
. . . . . . . . . . . . 13
⊢ (suc suc
𝑗 ∈ ω → suc
suc 𝑗 ∈
Fin) | 
| 45 | 43, 44 | syl 14 | 
. . . . . . . . . . . 12
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → suc suc 𝑗 ∈ Fin) | 
| 46 | 10 | ad2antrr 488 | 
. . . . . . . . . . . . . . . 16
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc suc 𝑗) → 𝐹:ω⟶2o) | 
| 47 |   | simpr 110 | 
. . . . . . . . . . . . . . . . 17
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc suc 𝑗) → 𝑥 ∈ suc suc 𝑗) | 
| 48 | 43 | adantr 276 | 
. . . . . . . . . . . . . . . . 17
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc suc 𝑗) → suc suc 𝑗 ∈ ω) | 
| 49 |   | elnn 4642 | 
. . . . . . . . . . . . . . . . 17
⊢ ((𝑥 ∈ suc suc 𝑗 ∧ suc suc 𝑗 ∈ ω) → 𝑥 ∈
ω) | 
| 50 | 47, 48, 49 | syl2anc 411 | 
. . . . . . . . . . . . . . . 16
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc suc 𝑗) → 𝑥 ∈ ω) | 
| 51 | 46, 50 | ffvelcdmd 5698 | 
. . . . . . . . . . . . . . 15
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc suc 𝑗) → (𝐹‘𝑥) ∈ 2o) | 
| 52 | 9, 51 | sselid 3181 | 
. . . . . . . . . . . . . 14
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc suc 𝑗) → (𝐹‘𝑥) ∈ ω) | 
| 53 | 18 | a1i 9 | 
. . . . . . . . . . . . . 14
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc suc 𝑗) → ∅ ∈
ω) | 
| 54 | 52, 53, 20 | syl2anc 411 | 
. . . . . . . . . . . . 13
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc suc 𝑗) → DECID (𝐹‘𝑥) = ∅) | 
| 55 | 54 | ralrimiva 2570 | 
. . . . . . . . . . . 12
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → ∀𝑥 ∈ suc suc 𝑗DECID (𝐹‘𝑥) = ∅) | 
| 56 |   | finexdc 6963 | 
. . . . . . . . . . . 12
⊢ ((suc suc
𝑗 ∈ Fin ∧
∀𝑥 ∈ suc suc
𝑗DECID
(𝐹‘𝑥) = ∅) → DECID
∃𝑥 ∈ suc suc
𝑗(𝐹‘𝑥) = ∅) | 
| 57 | 45, 55, 56 | syl2anc 411 | 
. . . . . . . . . . 11
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → DECID
∃𝑥 ∈ suc suc
𝑗(𝐹‘𝑥) = ∅) | 
| 58 | 40, 41, 57 | ifcldcd 3597 | 
. . . . . . . . . 10
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → if(∃𝑥 ∈ suc suc 𝑗(𝐹‘𝑥) = ∅, ∅, 1o) ∈
2o) | 
| 59 | 26, 37, 39, 58 | fvmptd3 5655 | 
. . . . . . . . 9
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → (𝐺‘suc 𝑗) = if(∃𝑥 ∈ suc suc 𝑗(𝐹‘𝑥) = ∅, ∅,
1o)) | 
| 60 |   | df-suc 4406 | 
. . . . . . . . . . . 12
⊢ suc suc
𝑗 = (suc 𝑗 ∪ {suc 𝑗}) | 
| 61 | 60 | rexeqi 2698 | 
. . . . . . . . . . 11
⊢
(∃𝑥 ∈ suc
suc 𝑗(𝐹‘𝑥) = ∅ ↔ ∃𝑥 ∈ (suc 𝑗 ∪ {suc 𝑗})(𝐹‘𝑥) = ∅) | 
| 62 |   | rexun 3343 | 
. . . . . . . . . . 11
⊢
(∃𝑥 ∈
(suc 𝑗 ∪ {suc 𝑗})(𝐹‘𝑥) = ∅ ↔ (∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅ ∨ ∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅)) | 
| 63 | 61, 62 | bitri 184 | 
. . . . . . . . . 10
⊢
(∃𝑥 ∈ suc
suc 𝑗(𝐹‘𝑥) = ∅ ↔ (∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅ ∨ ∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅)) | 
| 64 |   | ifbi 3581 | 
. . . . . . . . . 10
⊢
((∃𝑥 ∈
suc suc 𝑗(𝐹‘𝑥) = ∅ ↔ (∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅ ∨ ∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅)) → if(∃𝑥 ∈ suc suc 𝑗(𝐹‘𝑥) = ∅, ∅, 1o) =
if((∃𝑥 ∈ suc
𝑗(𝐹‘𝑥) = ∅ ∨ ∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅), ∅,
1o)) | 
| 65 | 63, 64 | ax-mp 5 | 
. . . . . . . . 9
⊢
if(∃𝑥 ∈
suc suc 𝑗(𝐹‘𝑥) = ∅, ∅, 1o) =
if((∃𝑥 ∈ suc
𝑗(𝐹‘𝑥) = ∅ ∨ ∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅), ∅,
1o) | 
| 66 | 59, 65 | eqtrdi 2245 | 
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → (𝐺‘suc 𝑗) = if((∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅ ∨ ∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅), ∅,
1o)) | 
| 67 |   | nnfi 6933 | 
. . . . . . . . . . 11
⊢ (suc
𝑗 ∈ ω → suc
𝑗 ∈
Fin) | 
| 68 | 39, 67 | syl 14 | 
. . . . . . . . . 10
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → suc 𝑗 ∈ Fin) | 
| 69 | 10 | ad2antrr 488 | 
. . . . . . . . . . . . . 14
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc 𝑗) → 𝐹:ω⟶2o) | 
| 70 |   | simpr 110 | 
. . . . . . . . . . . . . . 15
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc 𝑗) → 𝑥 ∈ suc 𝑗) | 
| 71 | 39 | adantr 276 | 
. . . . . . . . . . . . . . 15
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc 𝑗) → suc 𝑗 ∈ ω) | 
| 72 |   | elnn 4642 | 
. . . . . . . . . . . . . . 15
⊢ ((𝑥 ∈ suc 𝑗 ∧ suc 𝑗 ∈ ω) → 𝑥 ∈ ω) | 
| 73 | 70, 71, 72 | syl2anc 411 | 
. . . . . . . . . . . . . 14
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc 𝑗) → 𝑥 ∈ ω) | 
| 74 | 69, 73 | ffvelcdmd 5698 | 
. . . . . . . . . . . . 13
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc 𝑗) → (𝐹‘𝑥) ∈ 2o) | 
| 75 | 9, 74 | sselid 3181 | 
. . . . . . . . . . . 12
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc 𝑗) → (𝐹‘𝑥) ∈ ω) | 
| 76 | 18 | a1i 9 | 
. . . . . . . . . . . 12
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc 𝑗) → ∅ ∈
ω) | 
| 77 | 75, 76, 20 | syl2anc 411 | 
. . . . . . . . . . 11
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ 𝑥 ∈ suc 𝑗) → DECID (𝐹‘𝑥) = ∅) | 
| 78 | 77 | ralrimiva 2570 | 
. . . . . . . . . 10
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → ∀𝑥 ∈ suc 𝑗DECID (𝐹‘𝑥) = ∅) | 
| 79 |   | finexdc 6963 | 
. . . . . . . . . 10
⊢ ((suc
𝑗 ∈ Fin ∧
∀𝑥 ∈ suc 𝑗DECID (𝐹‘𝑥) = ∅) → DECID
∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) | 
| 80 | 68, 78, 79 | syl2anc 411 | 
. . . . . . . . 9
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → DECID
∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) | 
| 81 |   | ifordc 3600 | 
. . . . . . . . 9
⊢
(DECID ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅ → if((∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅ ∨ ∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅), ∅, 1o) =
if(∃𝑥 ∈ suc
𝑗(𝐹‘𝑥) = ∅, ∅, if(∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅, ∅,
1o))) | 
| 82 | 80, 81 | syl 14 | 
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → if((∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅ ∨ ∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅), ∅, 1o) =
if(∃𝑥 ∈ suc
𝑗(𝐹‘𝑥) = ∅, ∅, if(∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅, ∅,
1o))) | 
| 83 | 66, 82 | eqtrd 2229 | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → (𝐺‘suc 𝑗) = if(∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅, ∅, if(∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅, ∅,
1o))) | 
| 84 | 83 | adantr 276 | 
. . . . . 6
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → (𝐺‘suc 𝑗) = if(∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅, ∅, if(∃𝑥 ∈ {suc 𝑗} (𝐹‘𝑥) = ∅, ∅,
1o))) | 
| 85 |   | suceq 4437 | 
. . . . . . . . . . 11
⊢ (𝑖 = 𝑗 → suc 𝑖 = suc 𝑗) | 
| 86 | 85 | rexeqdv 2700 | 
. . . . . . . . . 10
⊢ (𝑖 = 𝑗 → (∃𝑥 ∈ suc 𝑖(𝐹‘𝑥) = ∅ ↔ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅)) | 
| 87 | 86 | ifbid 3582 | 
. . . . . . . . 9
⊢ (𝑖 = 𝑗 → if(∃𝑥 ∈ suc 𝑖(𝐹‘𝑥) = ∅, ∅, 1o) =
if(∃𝑥 ∈ suc
𝑗(𝐹‘𝑥) = ∅, ∅,
1o)) | 
| 88 |   | simpr 110 | 
. . . . . . . . 9
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → 𝑗 ∈ ω) | 
| 89 | 40, 41, 80 | ifcldcd 3597 | 
. . . . . . . . 9
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → if(∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅, ∅, 1o) ∈
2o) | 
| 90 | 26, 87, 88, 89 | fvmptd3 5655 | 
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → (𝐺‘𝑗) = if(∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅, ∅,
1o)) | 
| 91 | 90 | adantr 276 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → (𝐺‘𝑗) = if(∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅, ∅,
1o)) | 
| 92 | 33 | iftrued 3568 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → if(∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅, ∅, 1o) =
∅) | 
| 93 | 91, 92 | eqtrd 2229 | 
. . . . . 6
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → (𝐺‘𝑗) = ∅) | 
| 94 | 34, 84, 93 | 3eqtr4d 2239 | 
. . . . 5
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → (𝐺‘suc 𝑗) = (𝐺‘𝑗)) | 
| 95 |   | eqimss 3237 | 
. . . . 5
⊢ ((𝐺‘suc 𝑗) = (𝐺‘𝑗) → (𝐺‘suc 𝑗) ⊆ (𝐺‘𝑗)) | 
| 96 | 94, 95 | syl 14 | 
. . . 4
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → (𝐺‘suc 𝑗) ⊆ (𝐺‘𝑗)) | 
| 97 | 59, 58 | eqeltrd 2273 | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → (𝐺‘suc 𝑗) ∈ 2o) | 
| 98 |   | el2oss1o 6501 | 
. . . . . . 7
⊢ ((𝐺‘suc 𝑗) ∈ 2o → (𝐺‘suc 𝑗) ⊆ 1o) | 
| 99 | 97, 98 | syl 14 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → (𝐺‘suc 𝑗) ⊆ 1o) | 
| 100 | 99 | adantr 276 | 
. . . . 5
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ¬ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → (𝐺‘suc 𝑗) ⊆ 1o) | 
| 101 | 90 | adantr 276 | 
. . . . . 6
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ¬ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → (𝐺‘𝑗) = if(∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅, ∅,
1o)) | 
| 102 |   | simpr 110 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ¬ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → ¬ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) | 
| 103 | 102 | iffalsed 3571 | 
. . . . . 6
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ¬ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → if(∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅, ∅, 1o) =
1o) | 
| 104 | 101, 103 | eqtrd 2229 | 
. . . . 5
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ¬ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → (𝐺‘𝑗) = 1o) | 
| 105 | 100, 104 | sseqtrrd 3222 | 
. . . 4
⊢ (((𝜑 ∧ 𝑗 ∈ ω) ∧ ¬ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅) → (𝐺‘suc 𝑗) ⊆ (𝐺‘𝑗)) | 
| 106 |   | exmiddc 837 | 
. . . . 5
⊢
(DECID ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅ → (∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅ ∨ ¬ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅)) | 
| 107 | 80, 106 | syl 14 | 
. . . 4
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → (∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅ ∨ ¬ ∃𝑥 ∈ suc 𝑗(𝐹‘𝑥) = ∅)) | 
| 108 | 96, 105, 107 | mpjaodan 799 | 
. . 3
⊢ ((𝜑 ∧ 𝑗 ∈ ω) → (𝐺‘suc 𝑗) ⊆ (𝐺‘𝑗)) | 
| 109 | 108 | ralrimiva 2570 | 
. 2
⊢ (𝜑 → ∀𝑗 ∈ ω (𝐺‘suc 𝑗) ⊆ (𝐺‘𝑗)) | 
| 110 |   | fveq1 5557 | 
. . . . 5
⊢ (𝑓 = 𝐺 → (𝑓‘suc 𝑗) = (𝐺‘suc 𝑗)) | 
| 111 |   | fveq1 5557 | 
. . . . 5
⊢ (𝑓 = 𝐺 → (𝑓‘𝑗) = (𝐺‘𝑗)) | 
| 112 | 110, 111 | sseq12d 3214 | 
. . . 4
⊢ (𝑓 = 𝐺 → ((𝑓‘suc 𝑗) ⊆ (𝑓‘𝑗) ↔ (𝐺‘suc 𝑗) ⊆ (𝐺‘𝑗))) | 
| 113 | 112 | ralbidv 2497 | 
. . 3
⊢ (𝑓 = 𝐺 → (∀𝑗 ∈ ω (𝑓‘suc 𝑗) ⊆ (𝑓‘𝑗) ↔ ∀𝑗 ∈ ω (𝐺‘suc 𝑗) ⊆ (𝐺‘𝑗))) | 
| 114 |   | df-nninf 7186 | 
. . 3
⊢
ℕ∞ = {𝑓 ∈ (2o
↑𝑚 ω) ∣ ∀𝑗 ∈ ω (𝑓‘suc 𝑗) ⊆ (𝑓‘𝑗)} | 
| 115 | 113, 114 | elrab2 2923 | 
. 2
⊢ (𝐺 ∈
ℕ∞ ↔ (𝐺 ∈ (2o
↑𝑚 ω) ∧ ∀𝑗 ∈ ω (𝐺‘suc 𝑗) ⊆ (𝐺‘𝑗))) | 
| 116 | 32, 109, 115 | sylanbrc 417 | 
1
⊢ (𝜑 → 𝐺 ∈
ℕ∞) |