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| Mirrors > Home > ILE Home > Th. List > fxnn0nninf | GIF version | ||
| Description: A function from ℕ0* into ℕ∞. (Contributed by Jim Kingdon, 16-Jul-2022.) TODO: use infnninf 7190 instead of infnninfOLD 7191. More generally, this theorem and most theorems in this section could use an extended 𝐺 defined by 𝐺 = (frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ 〈ω, +∞〉) and 𝐹 = (𝑛 ∈ suc ω ↦ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑛, 1o, ∅))) as in nnnninf2 7193. | 
| Ref | Expression | 
|---|---|
| fxnn0nninf.g | ⊢ 𝐺 = frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) | 
| fxnn0nninf.f | ⊢ 𝐹 = (𝑛 ∈ ω ↦ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑛, 1o, ∅))) | 
| fxnn0nninf.i | ⊢ 𝐼 = ((𝐹 ∘ ◡𝐺) ∪ {〈+∞, (ω × {1o})〉}) | 
| Ref | Expression | 
|---|---|
| fxnn0nninf | ⊢ 𝐼:ℕ0*⟶ℕ∞ | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | fxnn0nninf.g | . . . . . 6 ⊢ 𝐺 = frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) | |
| 2 | fxnn0nninf.f | . . . . . 6 ⊢ 𝐹 = (𝑛 ∈ ω ↦ (𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑛, 1o, ∅))) | |
| 3 | 1, 2 | fnn0nninf 10530 | . . . . 5 ⊢ (𝐹 ∘ ◡𝐺):ℕ0⟶ℕ∞ | 
| 4 | pnfex 8080 | . . . . . . . 8 ⊢ +∞ ∈ V | |
| 5 | omex 4629 | . . . . . . . . 9 ⊢ ω ∈ V | |
| 6 | 1oex 6482 | . . . . . . . . . 10 ⊢ 1o ∈ V | |
| 7 | 6 | snex 4218 | . . . . . . . . 9 ⊢ {1o} ∈ V | 
| 8 | 5, 7 | xpex 4778 | . . . . . . . 8 ⊢ (ω × {1o}) ∈ V | 
| 9 | 4, 8 | f1osn 5544 | . . . . . . 7 ⊢ {〈+∞, (ω × {1o})〉}:{+∞}–1-1-onto→{(ω × {1o})} | 
| 10 | f1of 5504 | . . . . . . 7 ⊢ ({〈+∞, (ω × {1o})〉}:{+∞}–1-1-onto→{(ω × {1o})} → {〈+∞, (ω × {1o})〉}:{+∞}⟶{(ω × {1o})}) | |
| 11 | 9, 10 | ax-mp 5 | . . . . . 6 ⊢ {〈+∞, (ω × {1o})〉}:{+∞}⟶{(ω × {1o})} | 
| 12 | infnninfOLD 7191 | . . . . . . 7 ⊢ (ω × {1o}) ∈ ℕ∞ | |
| 13 | snssi 3766 | . . . . . . 7 ⊢ ((ω × {1o}) ∈ ℕ∞ → {(ω × {1o})} ⊆ ℕ∞) | |
| 14 | 12, 13 | ax-mp 5 | . . . . . 6 ⊢ {(ω × {1o})} ⊆ ℕ∞ | 
| 15 | fss 5419 | . . . . . 6 ⊢ (({〈+∞, (ω × {1o})〉}:{+∞}⟶{(ω × {1o})} ∧ {(ω × {1o})} ⊆ ℕ∞) → {〈+∞, (ω × {1o})〉}:{+∞}⟶ℕ∞) | |
| 16 | 11, 14, 15 | mp2an 426 | . . . . 5 ⊢ {〈+∞, (ω × {1o})〉}:{+∞}⟶ℕ∞ | 
| 17 | 3, 16 | pm3.2i 272 | . . . 4 ⊢ ((𝐹 ∘ ◡𝐺):ℕ0⟶ℕ∞ ∧ {〈+∞, (ω × {1o})〉}:{+∞}⟶ℕ∞) | 
| 18 | disj 3499 | . . . . 5 ⊢ ((ℕ0 ∩ {+∞}) = ∅ ↔ ∀𝑥 ∈ ℕ0 ¬ 𝑥 ∈ {+∞}) | |
| 19 | nn0nepnf 9320 | . . . . . . 7 ⊢ (𝑥 ∈ ℕ0 → 𝑥 ≠ +∞) | |
| 20 | 19 | neneqd 2388 | . . . . . 6 ⊢ (𝑥 ∈ ℕ0 → ¬ 𝑥 = +∞) | 
| 21 | elsni 3640 | . . . . . 6 ⊢ (𝑥 ∈ {+∞} → 𝑥 = +∞) | |
| 22 | 20, 21 | nsyl 629 | . . . . 5 ⊢ (𝑥 ∈ ℕ0 → ¬ 𝑥 ∈ {+∞}) | 
| 23 | 18, 22 | mprgbir 2555 | . . . 4 ⊢ (ℕ0 ∩ {+∞}) = ∅ | 
| 24 | fun2 5431 | . . . 4 ⊢ ((((𝐹 ∘ ◡𝐺):ℕ0⟶ℕ∞ ∧ {〈+∞, (ω × {1o})〉}:{+∞}⟶ℕ∞) ∧ (ℕ0 ∩ {+∞}) = ∅) → ((𝐹 ∘ ◡𝐺) ∪ {〈+∞, (ω × {1o})〉}):(ℕ0 ∪ {+∞})⟶ℕ∞) | |
| 25 | 17, 23, 24 | mp2an 426 | . . 3 ⊢ ((𝐹 ∘ ◡𝐺) ∪ {〈+∞, (ω × {1o})〉}):(ℕ0 ∪ {+∞})⟶ℕ∞ | 
| 26 | fxnn0nninf.i | . . . 4 ⊢ 𝐼 = ((𝐹 ∘ ◡𝐺) ∪ {〈+∞, (ω × {1o})〉}) | |
| 27 | 26 | feq1i 5400 | . . 3 ⊢ (𝐼:(ℕ0 ∪ {+∞})⟶ℕ∞ ↔ ((𝐹 ∘ ◡𝐺) ∪ {〈+∞, (ω × {1o})〉}):(ℕ0 ∪ {+∞})⟶ℕ∞) | 
| 28 | 25, 27 | mpbir 146 | . 2 ⊢ 𝐼:(ℕ0 ∪ {+∞})⟶ℕ∞ | 
| 29 | df-xnn0 9313 | . . 3 ⊢ ℕ0* = (ℕ0 ∪ {+∞}) | |
| 30 | 29 | feq2i 5401 | . 2 ⊢ (𝐼:ℕ0*⟶ℕ∞ ↔ 𝐼:(ℕ0 ∪ {+∞})⟶ℕ∞) | 
| 31 | 28, 30 | mpbir 146 | 1 ⊢ 𝐼:ℕ0*⟶ℕ∞ | 
| Colors of variables: wff set class | 
| Syntax hints: ¬ wn 3 ∧ wa 104 = wceq 1364 ∈ wcel 2167 ∪ cun 3155 ∩ cin 3156 ⊆ wss 3157 ∅c0 3450 ifcif 3561 {csn 3622 〈cop 3625 ↦ cmpt 4094 ωcom 4626 × cxp 4661 ◡ccnv 4662 ∘ ccom 4667 ⟶wf 5254 –1-1-onto→wf1o 5257 (class class class)co 5922 freccfrec 6448 1oc1o 6467 ℕ∞xnninf 7185 0cc0 7879 1c1 7880 + caddc 7882 +∞cpnf 8058 ℕ0cn0 9249 ℕ0*cxnn0 9312 ℤcz 9326 | 
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 106 ax-ia2 107 ax-ia3 108 ax-in1 615 ax-in2 616 ax-io 710 ax-5 1461 ax-7 1462 ax-gen 1463 ax-ie1 1507 ax-ie2 1508 ax-8 1518 ax-10 1519 ax-11 1520 ax-i12 1521 ax-bndl 1523 ax-4 1524 ax-17 1540 ax-i9 1544 ax-ial 1548 ax-i5r 1549 ax-13 2169 ax-14 2170 ax-ext 2178 ax-coll 4148 ax-sep 4151 ax-nul 4159 ax-pow 4207 ax-pr 4242 ax-un 4468 ax-setind 4573 ax-iinf 4624 ax-cnex 7970 ax-resscn 7971 ax-1cn 7972 ax-1re 7973 ax-icn 7974 ax-addcl 7975 ax-addrcl 7976 ax-mulcl 7977 ax-addcom 7979 ax-addass 7981 ax-distr 7983 ax-i2m1 7984 ax-0lt1 7985 ax-0id 7987 ax-rnegex 7988 ax-cnre 7990 ax-pre-ltirr 7991 ax-pre-ltwlin 7992 ax-pre-lttrn 7993 ax-pre-ltadd 7995 | 
| This theorem depends on definitions: df-bi 117 df-dc 836 df-3or 981 df-3an 982 df-tru 1367 df-fal 1370 df-nf 1475 df-sb 1777 df-eu 2048 df-mo 2049 df-clab 2183 df-cleq 2189 df-clel 2192 df-nfc 2328 df-ne 2368 df-nel 2463 df-ral 2480 df-rex 2481 df-reu 2482 df-rab 2484 df-v 2765 df-sbc 2990 df-csb 3085 df-dif 3159 df-un 3161 df-in 3163 df-ss 3170 df-nul 3451 df-if 3562 df-pw 3607 df-sn 3628 df-pr 3629 df-op 3631 df-uni 3840 df-int 3875 df-iun 3918 df-br 4034 df-opab 4095 df-mpt 4096 df-tr 4132 df-id 4328 df-iord 4401 df-on 4403 df-ilim 4404 df-suc 4406 df-iom 4627 df-xp 4669 df-rel 4670 df-cnv 4671 df-co 4672 df-dm 4673 df-rn 4674 df-res 4675 df-ima 4676 df-iota 5219 df-fun 5260 df-fn 5261 df-f 5262 df-f1 5263 df-fo 5264 df-f1o 5265 df-fv 5266 df-riota 5877 df-ov 5925 df-oprab 5926 df-mpo 5927 df-recs 6363 df-frec 6449 df-1o 6474 df-2o 6475 df-map 6709 df-nninf 7186 df-pnf 8063 df-mnf 8064 df-xr 8065 df-ltxr 8066 df-le 8067 df-sub 8199 df-neg 8200 df-inn 8991 df-n0 9250 df-xnn0 9313 df-z 9327 df-uz 9602 | 
| This theorem is referenced by: nninfctlemfo 12207 | 
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