| Step | Hyp | Ref
 | Expression | 
| 1 |   | peano4nninf.s | 
. . 3
⊢ 𝑆 = (𝑝 ∈ ℕ∞ ↦
(𝑖 ∈ ω ↦
if(𝑖 = ∅,
1o, (𝑝‘∪ 𝑖)))) | 
| 2 | 1 | nnsf 15649 | 
. 2
⊢ 𝑆:ℕ∞⟶ℕ∞ | 
| 3 |   | fveq1 5557 | 
. . . . . . . . . . 11
⊢ (𝑓 = 𝑥 → (𝑓‘suc 𝑗) = (𝑥‘suc 𝑗)) | 
| 4 |   | fveq1 5557 | 
. . . . . . . . . . 11
⊢ (𝑓 = 𝑥 → (𝑓‘𝑗) = (𝑥‘𝑗)) | 
| 5 | 3, 4 | sseq12d 3214 | 
. . . . . . . . . 10
⊢ (𝑓 = 𝑥 → ((𝑓‘suc 𝑗) ⊆ (𝑓‘𝑗) ↔ (𝑥‘suc 𝑗) ⊆ (𝑥‘𝑗))) | 
| 6 | 5 | ralbidv 2497 | 
. . . . . . . . 9
⊢ (𝑓 = 𝑥 → (∀𝑗 ∈ ω (𝑓‘suc 𝑗) ⊆ (𝑓‘𝑗) ↔ ∀𝑗 ∈ ω (𝑥‘suc 𝑗) ⊆ (𝑥‘𝑗))) | 
| 7 |   | df-nninf 7186 | 
. . . . . . . . 9
⊢
ℕ∞ = {𝑓 ∈ (2o
↑𝑚 ω) ∣ ∀𝑗 ∈ ω (𝑓‘suc 𝑗) ⊆ (𝑓‘𝑗)} | 
| 8 | 6, 7 | elrab2 2923 | 
. . . . . . . 8
⊢ (𝑥 ∈
ℕ∞ ↔ (𝑥 ∈ (2o
↑𝑚 ω) ∧ ∀𝑗 ∈ ω (𝑥‘suc 𝑗) ⊆ (𝑥‘𝑗))) | 
| 9 | 8 | simplbi 274 | 
. . . . . . 7
⊢ (𝑥 ∈
ℕ∞ → 𝑥 ∈ (2o
↑𝑚 ω)) | 
| 10 |   | elmapfn 6730 | 
. . . . . . 7
⊢ (𝑥 ∈ (2o
↑𝑚 ω) → 𝑥 Fn ω) | 
| 11 | 9, 10 | syl 14 | 
. . . . . 6
⊢ (𝑥 ∈
ℕ∞ → 𝑥 Fn ω) | 
| 12 | 11 | ad2antrr 488 | 
. . . . 5
⊢ (((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) → 𝑥 Fn ω) | 
| 13 |   | fveq1 5557 | 
. . . . . . . . . . 11
⊢ (𝑓 = 𝑦 → (𝑓‘suc 𝑗) = (𝑦‘suc 𝑗)) | 
| 14 |   | fveq1 5557 | 
. . . . . . . . . . 11
⊢ (𝑓 = 𝑦 → (𝑓‘𝑗) = (𝑦‘𝑗)) | 
| 15 | 13, 14 | sseq12d 3214 | 
. . . . . . . . . 10
⊢ (𝑓 = 𝑦 → ((𝑓‘suc 𝑗) ⊆ (𝑓‘𝑗) ↔ (𝑦‘suc 𝑗) ⊆ (𝑦‘𝑗))) | 
| 16 | 15 | ralbidv 2497 | 
. . . . . . . . 9
⊢ (𝑓 = 𝑦 → (∀𝑗 ∈ ω (𝑓‘suc 𝑗) ⊆ (𝑓‘𝑗) ↔ ∀𝑗 ∈ ω (𝑦‘suc 𝑗) ⊆ (𝑦‘𝑗))) | 
| 17 | 16, 7 | elrab2 2923 | 
. . . . . . . 8
⊢ (𝑦 ∈
ℕ∞ ↔ (𝑦 ∈ (2o
↑𝑚 ω) ∧ ∀𝑗 ∈ ω (𝑦‘suc 𝑗) ⊆ (𝑦‘𝑗))) | 
| 18 | 17 | simplbi 274 | 
. . . . . . 7
⊢ (𝑦 ∈
ℕ∞ → 𝑦 ∈ (2o
↑𝑚 ω)) | 
| 19 |   | elmapfn 6730 | 
. . . . . . 7
⊢ (𝑦 ∈ (2o
↑𝑚 ω) → 𝑦 Fn ω) | 
| 20 | 18, 19 | syl 14 | 
. . . . . 6
⊢ (𝑦 ∈
ℕ∞ → 𝑦 Fn ω) | 
| 21 | 20 | ad2antlr 489 | 
. . . . 5
⊢ (((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) → 𝑦 Fn ω) | 
| 22 |   | simplr 528 | 
. . . . . . 7
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → (𝑆‘𝑥) = (𝑆‘𝑦)) | 
| 23 | 22 | fveq1d 5560 | 
. . . . . 6
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → ((𝑆‘𝑥)‘suc 𝑘) = ((𝑆‘𝑦)‘suc 𝑘)) | 
| 24 |   | fveq1 5557 | 
. . . . . . . . . . . 12
⊢ (𝑝 = 𝑥 → (𝑝‘∪ 𝑖) = (𝑥‘∪ 𝑖)) | 
| 25 | 24 | ifeq2d 3579 | 
. . . . . . . . . . 11
⊢ (𝑝 = 𝑥 → if(𝑖 = ∅, 1o, (𝑝‘∪ 𝑖))
= if(𝑖 = ∅,
1o, (𝑥‘∪ 𝑖))) | 
| 26 | 25 | mpteq2dv 4124 | 
. . . . . . . . . 10
⊢ (𝑝 = 𝑥 → (𝑖 ∈ ω ↦ if(𝑖 = ∅, 1o, (𝑝‘∪ 𝑖)))
= (𝑖 ∈ ω ↦
if(𝑖 = ∅,
1o, (𝑥‘∪ 𝑖)))) | 
| 27 |   | omex 4629 | 
. . . . . . . . . . 11
⊢ ω
∈ V | 
| 28 | 27 | mptex 5788 | 
. . . . . . . . . 10
⊢ (𝑖 ∈ ω ↦ if(𝑖 = ∅, 1o,
(𝑥‘∪ 𝑖)))
∈ V | 
| 29 | 26, 1, 28 | fvmpt 5638 | 
. . . . . . . . 9
⊢ (𝑥 ∈
ℕ∞ → (𝑆‘𝑥) = (𝑖 ∈ ω ↦ if(𝑖 = ∅, 1o, (𝑥‘∪ 𝑖)))) | 
| 30 | 29 | ad3antrrr 492 | 
. . . . . . . 8
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → (𝑆‘𝑥) = (𝑖 ∈ ω ↦ if(𝑖 = ∅, 1o, (𝑥‘∪ 𝑖)))) | 
| 31 |   | simpr 110 | 
. . . . . . . . . 10
⊢
(((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) ∧ 𝑖 = suc 𝑘) → 𝑖 = suc 𝑘) | 
| 32 | 31 | eqeq1d 2205 | 
. . . . . . . . 9
⊢
(((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) ∧ 𝑖 = suc 𝑘) → (𝑖 = ∅ ↔ suc 𝑘 = ∅)) | 
| 33 | 31 | unieqd 3850 | 
. . . . . . . . . 10
⊢
(((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) ∧ 𝑖 = suc 𝑘) → ∪ 𝑖 = ∪
suc 𝑘) | 
| 34 | 33 | fveq2d 5562 | 
. . . . . . . . 9
⊢
(((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) ∧ 𝑖 = suc 𝑘) → (𝑥‘∪ 𝑖) = (𝑥‘∪ suc 𝑘)) | 
| 35 | 32, 34 | ifbieq2d 3585 | 
. . . . . . . 8
⊢
(((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) ∧ 𝑖 = suc 𝑘) → if(𝑖 = ∅, 1o, (𝑥‘∪ 𝑖))
= if(suc 𝑘 = ∅,
1o, (𝑥‘∪ suc 𝑘))) | 
| 36 |   | peano2 4631 | 
. . . . . . . . 9
⊢ (𝑘 ∈ ω → suc 𝑘 ∈
ω) | 
| 37 | 36 | adantl 277 | 
. . . . . . . 8
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → suc 𝑘 ∈
ω) | 
| 38 |   | 1lt2o 6500 | 
. . . . . . . . . 10
⊢
1o ∈ 2o | 
| 39 | 38 | a1i 9 | 
. . . . . . . . 9
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → 1o ∈
2o) | 
| 40 |   | nninff 7188 | 
. . . . . . . . . . 11
⊢ (𝑥 ∈
ℕ∞ → 𝑥:ω⟶2o) | 
| 41 | 40 | ad3antrrr 492 | 
. . . . . . . . . 10
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → 𝑥:ω⟶2o) | 
| 42 |   | nnpredcl 4659 | 
. . . . . . . . . . 11
⊢ (suc
𝑘 ∈ ω →
∪ suc 𝑘 ∈ ω) | 
| 43 | 37, 42 | syl 14 | 
. . . . . . . . . 10
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → ∪ suc 𝑘 ∈ ω) | 
| 44 | 41, 43 | ffvelcdmd 5698 | 
. . . . . . . . 9
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → (𝑥‘∪ suc 𝑘) ∈
2o) | 
| 45 |   | nndceq0 4654 | 
. . . . . . . . . 10
⊢ (suc
𝑘 ∈ ω →
DECID suc 𝑘
= ∅) | 
| 46 | 37, 45 | syl 14 | 
. . . . . . . . 9
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → DECID
suc 𝑘 =
∅) | 
| 47 | 39, 44, 46 | ifcldcd 3597 | 
. . . . . . . 8
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → if(suc 𝑘 = ∅, 1o,
(𝑥‘∪ suc 𝑘)) ∈ 2o) | 
| 48 | 30, 35, 37, 47 | fvmptd 5642 | 
. . . . . . 7
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → ((𝑆‘𝑥)‘suc 𝑘) = if(suc 𝑘 = ∅, 1o, (𝑥‘∪ suc 𝑘))) | 
| 49 |   | peano3 4632 | 
. . . . . . . . . 10
⊢ (𝑘 ∈ ω → suc 𝑘 ≠ ∅) | 
| 50 | 49 | adantl 277 | 
. . . . . . . . 9
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → suc 𝑘 ≠ ∅) | 
| 51 | 50 | neneqd 2388 | 
. . . . . . . 8
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → ¬ suc 𝑘 = ∅) | 
| 52 | 51 | iffalsed 3571 | 
. . . . . . 7
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → if(suc 𝑘 = ∅, 1o,
(𝑥‘∪ suc 𝑘)) = (𝑥‘∪ suc 𝑘)) | 
| 53 |   | nnord 4648 | 
. . . . . . . . . . 11
⊢ (𝑘 ∈ ω → Ord 𝑘) | 
| 54 |   | ordtr 4413 | 
. . . . . . . . . . 11
⊢ (Ord
𝑘 → Tr 𝑘) | 
| 55 | 53, 54 | syl 14 | 
. . . . . . . . . 10
⊢ (𝑘 ∈ ω → Tr 𝑘) | 
| 56 |   | unisucg 4449 | 
. . . . . . . . . 10
⊢ (𝑘 ∈ ω → (Tr 𝑘 ↔ ∪ suc 𝑘 = 𝑘)) | 
| 57 | 55, 56 | mpbid 147 | 
. . . . . . . . 9
⊢ (𝑘 ∈ ω → ∪ suc 𝑘 = 𝑘) | 
| 58 | 57 | fveq2d 5562 | 
. . . . . . . 8
⊢ (𝑘 ∈ ω → (𝑥‘∪ suc 𝑘) = (𝑥‘𝑘)) | 
| 59 | 58 | adantl 277 | 
. . . . . . 7
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → (𝑥‘∪ suc 𝑘) = (𝑥‘𝑘)) | 
| 60 | 48, 52, 59 | 3eqtrd 2233 | 
. . . . . 6
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → ((𝑆‘𝑥)‘suc 𝑘) = (𝑥‘𝑘)) | 
| 61 |   | fveq1 5557 | 
. . . . . . . . . . . 12
⊢ (𝑝 = 𝑦 → (𝑝‘∪ 𝑖) = (𝑦‘∪ 𝑖)) | 
| 62 | 61 | ifeq2d 3579 | 
. . . . . . . . . . 11
⊢ (𝑝 = 𝑦 → if(𝑖 = ∅, 1o, (𝑝‘∪ 𝑖))
= if(𝑖 = ∅,
1o, (𝑦‘∪ 𝑖))) | 
| 63 | 62 | mpteq2dv 4124 | 
. . . . . . . . . 10
⊢ (𝑝 = 𝑦 → (𝑖 ∈ ω ↦ if(𝑖 = ∅, 1o, (𝑝‘∪ 𝑖)))
= (𝑖 ∈ ω ↦
if(𝑖 = ∅,
1o, (𝑦‘∪ 𝑖)))) | 
| 64 | 27 | mptex 5788 | 
. . . . . . . . . 10
⊢ (𝑖 ∈ ω ↦ if(𝑖 = ∅, 1o,
(𝑦‘∪ 𝑖)))
∈ V | 
| 65 | 63, 1, 64 | fvmpt 5638 | 
. . . . . . . . 9
⊢ (𝑦 ∈
ℕ∞ → (𝑆‘𝑦) = (𝑖 ∈ ω ↦ if(𝑖 = ∅, 1o, (𝑦‘∪ 𝑖)))) | 
| 66 | 65 | ad3antlr 493 | 
. . . . . . . 8
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → (𝑆‘𝑦) = (𝑖 ∈ ω ↦ if(𝑖 = ∅, 1o, (𝑦‘∪ 𝑖)))) | 
| 67 | 33 | fveq2d 5562 | 
. . . . . . . . 9
⊢
(((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) ∧ 𝑖 = suc 𝑘) → (𝑦‘∪ 𝑖) = (𝑦‘∪ suc 𝑘)) | 
| 68 | 32, 67 | ifbieq2d 3585 | 
. . . . . . . 8
⊢
(((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) ∧ 𝑖 = suc 𝑘) → if(𝑖 = ∅, 1o, (𝑦‘∪ 𝑖))
= if(suc 𝑘 = ∅,
1o, (𝑦‘∪ suc 𝑘))) | 
| 69 |   | nninff 7188 | 
. . . . . . . . . . 11
⊢ (𝑦 ∈
ℕ∞ → 𝑦:ω⟶2o) | 
| 70 | 69 | ad3antlr 493 | 
. . . . . . . . . 10
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → 𝑦:ω⟶2o) | 
| 71 | 70, 43 | ffvelcdmd 5698 | 
. . . . . . . . 9
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → (𝑦‘∪ suc 𝑘) ∈
2o) | 
| 72 | 39, 71, 46 | ifcldcd 3597 | 
. . . . . . . 8
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → if(suc 𝑘 = ∅, 1o,
(𝑦‘∪ suc 𝑘)) ∈ 2o) | 
| 73 | 66, 68, 37, 72 | fvmptd 5642 | 
. . . . . . 7
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → ((𝑆‘𝑦)‘suc 𝑘) = if(suc 𝑘 = ∅, 1o, (𝑦‘∪ suc 𝑘))) | 
| 74 | 51 | iffalsed 3571 | 
. . . . . . 7
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → if(suc 𝑘 = ∅, 1o,
(𝑦‘∪ suc 𝑘)) = (𝑦‘∪ suc 𝑘)) | 
| 75 | 57 | fveq2d 5562 | 
. . . . . . . 8
⊢ (𝑘 ∈ ω → (𝑦‘∪ suc 𝑘) = (𝑦‘𝑘)) | 
| 76 | 75 | adantl 277 | 
. . . . . . 7
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → (𝑦‘∪ suc 𝑘) = (𝑦‘𝑘)) | 
| 77 | 73, 74, 76 | 3eqtrd 2233 | 
. . . . . 6
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → ((𝑆‘𝑦)‘suc 𝑘) = (𝑦‘𝑘)) | 
| 78 | 23, 60, 77 | 3eqtr3d 2237 | 
. . . . 5
⊢ ((((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) ∧ 𝑘 ∈ ω) → (𝑥‘𝑘) = (𝑦‘𝑘)) | 
| 79 | 12, 21, 78 | eqfnfvd 5662 | 
. . . 4
⊢ (((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) ∧
(𝑆‘𝑥) = (𝑆‘𝑦)) → 𝑥 = 𝑦) | 
| 80 | 79 | ex 115 | 
. . 3
⊢ ((𝑥 ∈
ℕ∞ ∧ 𝑦 ∈ ℕ∞) →
((𝑆‘𝑥) = (𝑆‘𝑦) → 𝑥 = 𝑦)) | 
| 81 | 80 | rgen2a 2551 | 
. 2
⊢
∀𝑥 ∈
ℕ∞ ∀𝑦 ∈ ℕ∞ ((𝑆‘𝑥) = (𝑆‘𝑦) → 𝑥 = 𝑦) | 
| 82 |   | dff13 5815 | 
. 2
⊢ (𝑆:ℕ∞–1-1→ℕ∞ ↔
(𝑆:ℕ∞⟶ℕ∞
∧ ∀𝑥 ∈
ℕ∞ ∀𝑦 ∈
ℕ∞ ((𝑆‘𝑥) = (𝑆‘𝑦)
→ 𝑥 = 𝑦))) | 
| 83 | 2, 81, 82 | mpbir2an 944 | 
1
⊢ 𝑆:ℕ∞–1-1→ℕ∞ |