Theorem nninfall 16632

Description: Given a decidable predicate on ℕ_∞, showing it holds for natural numbers and the point at infinity suffices to show it holds everywhere. The sense in which 𝑄 is a decidable predicate is that it assigns a value of either ∅ or 1_o (which can be thought of as false and true) to every element of ℕ_∞. Lemma 3.5 of [PradicBrown2022], p. 5. (Contributed by Jim Kingdon, 1-Aug-2022.)

Hypotheses

Ref	Expression
nninfall.q	⊢ (𝜑 → 𝑄 ∈ (2o ↑𝑚 ℕ∞))
nninfall.inf	⊢ (𝜑 → (𝑄‘(𝑥 ∈ ω ↦ 1o)) = 1o)
nninfall.n	⊢ (𝜑 → ∀𝑛 ∈ ω (𝑄‘(𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑛, 1o, ∅))) = 1o)

Assertion

Ref	Expression
nninfall	⊢ (𝜑 → ∀𝑝 ∈ ℕ∞ (𝑄‘𝑝) = 1o)

Distinct variable groups:   𝑄,𝑛,𝑖   𝑛,𝑝,𝑖,𝜑

Allowed substitution hints:   𝜑(𝑥)   𝑄(𝑥,𝑝)

Proof of Theorem nninfall

Dummy variables 𝑎 𝑏 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		1n0 6600	. . . . 5 ⊢ 1o ≠ ∅
2	1	nesymi 2448	. . . 4 ⊢ ¬ ∅ = 1o
3		simplr 529	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → 𝑝 ∈ ℕ∞)
4		nninff 7321	. . . . . . . . . . . 12 ⊢ (𝑝 ∈ ℕ∞ → 𝑝:ω⟶2o)
5	4	ffnd 5483	. . . . . . . . . . 11 ⊢ (𝑝 ∈ ℕ∞ → 𝑝 Fn ω)
6	3, 5	syl 14	. . . . . . . . . 10 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → 𝑝 Fn ω)
7		nninfall.q	. . . . . . . . . . . . . . 15 ⊢ (𝜑 → 𝑄 ∈ (2o ↑𝑚 ℕ∞))
8	7	ad2antrr 488	. . . . . . . . . . . . . 14 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → 𝑄 ∈ (2o ↑𝑚 ℕ∞))
9		nninfall.inf	. . . . . . . . . . . . . . 15 ⊢ (𝜑 → (𝑄‘(𝑥 ∈ ω ↦ 1o)) = 1o)
10	9	ad2antrr 488	. . . . . . . . . . . . . 14 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → (𝑄‘(𝑥 ∈ ω ↦ 1o)) = 1o)
11		nninfall.n	. . . . . . . . . . . . . . 15 ⊢ (𝜑 → ∀𝑛 ∈ ω (𝑄‘(𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑛, 1o, ∅))) = 1o)
12	11	ad2antrr 488	. . . . . . . . . . . . . 14 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → ∀𝑛 ∈ ω (𝑄‘(𝑖 ∈ ω ↦ if(𝑖 ∈ 𝑛, 1o, ∅))) = 1o)
13		simpr 110	. . . . . . . . . . . . . 14 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → (𝑄‘𝑝) = ∅)
14	8, 10, 12, 3, 13	nninfalllem1 16631	. . . . . . . . . . . . 13 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → ∀𝑛 ∈ ω (𝑝‘𝑛) = 1o)
15		eqeq1 2238	. . . . . . . . . . . . . . 15 ⊢ (𝑎 = (𝑝‘𝑛) → (𝑎 = 1o ↔ (𝑝‘𝑛) = 1o))
16	15	ralrn 5785	. . . . . . . . . . . . . 14 ⊢ (𝑝 Fn ω → (∀𝑎 ∈ ran 𝑝 𝑎 = 1o ↔ ∀𝑛 ∈ ω (𝑝‘𝑛) = 1o))
17	3, 5, 16	3syl 17	. . . . . . . . . . . . 13 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → (∀𝑎 ∈ ran 𝑝 𝑎 = 1o ↔ ∀𝑛 ∈ ω (𝑝‘𝑛) = 1o))
18	14, 17	mpbird 167	. . . . . . . . . . . 12 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → ∀𝑎 ∈ ran 𝑝 𝑎 = 1o)
19		peano1 4692	. . . . . . . . . . . . . . . 16 ⊢ ∅ ∈ ω
20		elex2 2819	. . . . . . . . . . . . . . . 16 ⊢ (∅ ∈ ω → ∃𝑏 𝑏 ∈ ω)
21	19, 20	ax-mp 5	. . . . . . . . . . . . . . 15 ⊢ ∃𝑏 𝑏 ∈ ω
22		fdm 5488	. . . . . . . . . . . . . . . . 17 ⊢ (𝑝:ω⟶2o → dom 𝑝 = ω)
23	22	eleq2d 2301	. . . . . . . . . . . . . . . 16 ⊢ (𝑝:ω⟶2o → (𝑏 ∈ dom 𝑝 ↔ 𝑏 ∈ ω))
24	23	exbidv 1873	. . . . . . . . . . . . . . 15 ⊢ (𝑝:ω⟶2o → (∃𝑏 𝑏 ∈ dom 𝑝 ↔ ∃𝑏 𝑏 ∈ ω))
25	21, 24	mpbiri 168	. . . . . . . . . . . . . 14 ⊢ (𝑝:ω⟶2o → ∃𝑏 𝑏 ∈ dom 𝑝)
26		dmmrnm 4951	. . . . . . . . . . . . . . 15 ⊢ (∃𝑏 𝑏 ∈ dom 𝑝 ↔ ∃𝑎 𝑎 ∈ ran 𝑝)
27		eqsnm 3838	. . . . . . . . . . . . . . 15 ⊢ (∃𝑎 𝑎 ∈ ran 𝑝 → (ran 𝑝 = {1o} ↔ ∀𝑎 ∈ ran 𝑝 𝑎 = 1o))
28	26, 27	sylbi 121	. . . . . . . . . . . . . 14 ⊢ (∃𝑏 𝑏 ∈ dom 𝑝 → (ran 𝑝 = {1o} ↔ ∀𝑎 ∈ ran 𝑝 𝑎 = 1o))
29	25, 28	syl 14	. . . . . . . . . . . . 13 ⊢ (𝑝:ω⟶2o → (ran 𝑝 = {1o} ↔ ∀𝑎 ∈ ran 𝑝 𝑎 = 1o))
30	3, 4, 29	3syl 17	. . . . . . . . . . . 12 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → (ran 𝑝 = {1o} ↔ ∀𝑎 ∈ ran 𝑝 𝑎 = 1o))
31	18, 30	mpbird 167	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → ran 𝑝 = {1o})
32		eqimss 3281	. . . . . . . . . . 11 ⊢ (ran 𝑝 = {1o} → ran 𝑝 ⊆ {1o})
33	31, 32	syl 14	. . . . . . . . . 10 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → ran 𝑝 ⊆ {1o})
34		df-f 5330	. . . . . . . . . 10 ⊢ (𝑝:ω⟶{1o} ↔ (𝑝 Fn ω ∧ ran 𝑝 ⊆ {1o}))
35	6, 33, 34	sylanbrc 417	. . . . . . . . 9 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → 𝑝:ω⟶{1o})
36		1onn 6688	. . . . . . . . . 10 ⊢ 1o ∈ ω
37		fconst2g 5869	. . . . . . . . . 10 ⊢ (1o ∈ ω → (𝑝:ω⟶{1o} ↔ 𝑝 = (ω × {1o})))
38	36, 37	ax-mp 5	. . . . . . . . 9 ⊢ (𝑝:ω⟶{1o} ↔ 𝑝 = (ω × {1o}))
39	35, 38	sylib 122	. . . . . . . 8 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → 𝑝 = (ω × {1o}))
40		fconstmpt 4773	. . . . . . . 8 ⊢ (ω × {1o}) = (𝑥 ∈ ω ↦ 1o)
41	39, 40	eqtrdi 2280	. . . . . . 7 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → 𝑝 = (𝑥 ∈ ω ↦ 1o))
42	41	fveq2d 5643	. . . . . 6 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → (𝑄‘𝑝) = (𝑄‘(𝑥 ∈ ω ↦ 1o)))
43	42, 13, 10	3eqtr3d 2272	. . . . 5 ⊢ (((𝜑 ∧ 𝑝 ∈ ℕ∞) ∧ (𝑄‘𝑝) = ∅) → ∅ = 1o)
44	43	ex 115	. . . 4 ⊢ ((𝜑 ∧ 𝑝 ∈ ℕ∞) → ((𝑄‘𝑝) = ∅ → ∅ = 1o))
45	2, 44	mtoi 670	. . 3 ⊢ ((𝜑 ∧ 𝑝 ∈ ℕ∞) → ¬ (𝑄‘𝑝) = ∅)
46		elmapi 6839	. . . . . . 7 ⊢ (𝑄 ∈ (2o ↑𝑚 ℕ∞) → 𝑄:ℕ∞⟶2o)
47	7, 46	syl 14	. . . . . 6 ⊢ (𝜑 → 𝑄:ℕ∞⟶2o)
48	47	ffvelcdmda 5782	. . . . 5 ⊢ ((𝜑 ∧ 𝑝 ∈ ℕ∞) → (𝑄‘𝑝) ∈ 2o)
49		elpri 3692	. . . . . 6 ⊢ ((𝑄‘𝑝) ∈ {∅, 1o} → ((𝑄‘𝑝) = ∅ ∨ (𝑄‘𝑝) = 1o))
50		df2o3 6597	. . . . . 6 ⊢ 2o = {∅, 1o}
51	49, 50	eleq2s 2326	. . . . 5 ⊢ ((𝑄‘𝑝) ∈ 2o → ((𝑄‘𝑝) = ∅ ∨ (𝑄‘𝑝) = 1o))
52	48, 51	syl 14	. . . 4 ⊢ ((𝜑 ∧ 𝑝 ∈ ℕ∞) → ((𝑄‘𝑝) = ∅ ∨ (𝑄‘𝑝) = 1o))
53	52	orcomd 736	. . 3 ⊢ ((𝜑 ∧ 𝑝 ∈ ℕ∞) → ((𝑄‘𝑝) = 1o ∨ (𝑄‘𝑝) = ∅))
54	45, 53	ecased 1385	. 2 ⊢ ((𝜑 ∧ 𝑝 ∈ ℕ∞) → (𝑄‘𝑝) = 1o)
55	54	ralrimiva 2605	1 ⊢ (𝜑 → ∀𝑝 ∈ ℕ∞ (𝑄‘𝑝) = 1o)

Syntax hints:   → wi 4   ∧ wa 104   ↔ wb 105   ∨ wo 715   = wceq 1397  ∃wex 1540   ∈ wcel 2202  ∀wral 2510   ⊆ wss 3200  ∅c0 3494  ifcif 3605  {csn 3669  {cpr 3670   ↦ cmpt 4150  ωcom 4688   × cxp 4723  dom cdm 4725  ran crn 4726   Fn wfn 5321  ⟶wf 5322  ‘cfv 5326  (class class class)co 6018  1_oc1o 6575  2_oc2o 6576   ↑_𝑚 cmap 6817  ℕ_∞xnninf 7318

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 619  ax-in2 620  ax-io 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-13 2204  ax-14 2205  ax-ext 2213  ax-sep 4207  ax-nul 4215  ax-pow 4264  ax-pr 4299  ax-un 4530  ax-setind 4635  ax-iinf 4686

This theorem depends on definitions:  df-bi 117  df-dc 842  df-3or 1005  df-3an 1006  df-tru 1400  df-fal 1403  df-nf 1509  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-ne 2403  df-ral 2515  df-rex 2516  df-rab 2519  df-v 2804  df-sbc 3032  df-csb 3128  df-dif 3202  df-un 3204  df-in 3206  df-ss 3213  df-nul 3495  df-if 3606  df-pw 3654  df-sn 3675  df-pr 3676  df-op 3678  df-uni 3894  df-int 3929  df-br 4089  df-opab 4151  df-mpt 4152  df-tr 4188  df-id 4390  df-iord 4463  df-on 4465  df-suc 4468  df-iom 4689  df-xp 4731  df-rel 4732  df-cnv 4733  df-co 4734  df-dm 4735  df-rn 4736  df-iota 5286  df-fun 5328  df-fn 5329  df-f 5330  df-fv 5334  df-ov 6021  df-oprab 6022  df-mpo 6023  df-1o 6582  df-2o 6583  df-map 6819  df-nninf 7319

This theorem is referenced by:  nninfsel  16640  nninffeq  16643