Theorem axdclem2 9791

Description: Lemma for axdc 9792. Using the full Axiom of Choice, we can construct a choice function 𝑔 on 𝒫 dom 𝑥. From this, we can build a sequence 𝐹 starting at any value 𝑠 ∈ dom 𝑥 by repeatedly applying 𝑔 to the set (𝐹‘𝑥) (where 𝑥 is the value from the previous iteration). (Contributed by Mario Carneiro, 25-Jan-2013.)

Hypothesis

Ref	Expression
axdclem2.1	⊢ 𝐹 = (rec((𝑦 ∈ V ↦ (𝑔‘{𝑧 ∣ 𝑦𝑥𝑧})), 𝑠) ↾ ω)

Assertion

Ref	Expression
axdclem2	⊢ (∃𝑧 𝑠𝑥𝑧 → (ran 𝑥 ⊆ dom 𝑥 → ∃𝑓∀𝑛 ∈ ω (𝑓‘𝑛)𝑥(𝑓‘suc 𝑛)))

Distinct variable groups:   𝑓,𝐹,𝑛   𝑦,𝐹,𝑧,𝑛   𝑓,𝑔,𝑥,𝑛   𝑔,𝑠,𝑦,𝑛   𝑧,𝑔   𝑥,𝑦,𝑧

Allowed substitution hints:   𝐹(𝑥,𝑔,𝑠)

Proof of Theorem axdclem2

Dummy variable 𝑘 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		frfnom 7925	. . . . . . . 8 ⊢ (rec((𝑦 ∈ V ↦ (𝑔‘{𝑧 ∣ 𝑦𝑥𝑧})), 𝑠) ↾ ω) Fn ω
2		axdclem2.1	. . . . . . . . 9 ⊢ 𝐹 = (rec((𝑦 ∈ V ↦ (𝑔‘{𝑧 ∣ 𝑦𝑥𝑧})), 𝑠) ↾ ω)
3	2	fneq1i 6323	. . . . . . . 8 ⊢ (𝐹 Fn ω ↔ (rec((𝑦 ∈ V ↦ (𝑔‘{𝑧 ∣ 𝑦𝑥𝑧})), 𝑠) ↾ ω) Fn ω)
4	1, 3	mpbir 232	. . . . . . 7 ⊢ 𝐹 Fn ω
5	4	a1i 11	. . . . . 6 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → 𝐹 Fn ω)
6		fveq2 6541	. . . . . . . . . . 11 ⊢ (𝑛 = ∅ → (𝐹‘𝑛) = (𝐹‘∅))
7		suceq 6134	. . . . . . . . . . . 12 ⊢ (𝑛 = ∅ → suc 𝑛 = suc ∅)
8	7	fveq2d 6545	. . . . . . . . . . 11 ⊢ (𝑛 = ∅ → (𝐹‘suc 𝑛) = (𝐹‘suc ∅))
9	6, 8	breq12d 4977	. . . . . . . . . 10 ⊢ (𝑛 = ∅ → ((𝐹‘𝑛)𝑥(𝐹‘suc 𝑛) ↔ (𝐹‘∅)𝑥(𝐹‘suc ∅)))
10		fveq2 6541	. . . . . . . . . . 11 ⊢ (𝑛 = 𝑘 → (𝐹‘𝑛) = (𝐹‘𝑘))
11		suceq 6134	. . . . . . . . . . . 12 ⊢ (𝑛 = 𝑘 → suc 𝑛 = suc 𝑘)
12	11	fveq2d 6545	. . . . . . . . . . 11 ⊢ (𝑛 = 𝑘 → (𝐹‘suc 𝑛) = (𝐹‘suc 𝑘))
13	10, 12	breq12d 4977	. . . . . . . . . 10 ⊢ (𝑛 = 𝑘 → ((𝐹‘𝑛)𝑥(𝐹‘suc 𝑛) ↔ (𝐹‘𝑘)𝑥(𝐹‘suc 𝑘)))
14		fveq2 6541	. . . . . . . . . . 11 ⊢ (𝑛 = suc 𝑘 → (𝐹‘𝑛) = (𝐹‘suc 𝑘))
15		suceq 6134	. . . . . . . . . . . 12 ⊢ (𝑛 = suc 𝑘 → suc 𝑛 = suc suc 𝑘)
16	15	fveq2d 6545	. . . . . . . . . . 11 ⊢ (𝑛 = suc 𝑘 → (𝐹‘suc 𝑛) = (𝐹‘suc suc 𝑘))
17	14, 16	breq12d 4977	. . . . . . . . . 10 ⊢ (𝑛 = suc 𝑘 → ((𝐹‘𝑛)𝑥(𝐹‘suc 𝑛) ↔ (𝐹‘suc 𝑘)𝑥(𝐹‘suc suc 𝑘)))
18	2	fveq1i 6542	. . . . . . . . . . . . . . . 16 ⊢ (𝐹‘∅) = ((rec((𝑦 ∈ V ↦ (𝑔‘{𝑧 ∣ 𝑦𝑥𝑧})), 𝑠) ↾ ω)‘∅)
19		fr0g 7926	. . . . . . . . . . . . . . . . 17 ⊢ (𝑠 ∈ V → ((rec((𝑦 ∈ V ↦ (𝑔‘{𝑧 ∣ 𝑦𝑥𝑧})), 𝑠) ↾ ω)‘∅) = 𝑠)
20	19	elv 3441	. . . . . . . . . . . . . . . 16 ⊢ ((rec((𝑦 ∈ V ↦ (𝑔‘{𝑧 ∣ 𝑦𝑥𝑧})), 𝑠) ↾ ω)‘∅) = 𝑠
21	18, 20	eqtri 2818	. . . . . . . . . . . . . . 15 ⊢ (𝐹‘∅) = 𝑠
22	21	breq1i 4971	. . . . . . . . . . . . . 14 ⊢ ((𝐹‘∅)𝑥𝑧 ↔ 𝑠𝑥𝑧)
23	22	biimpri 229	. . . . . . . . . . . . 13 ⊢ (𝑠𝑥𝑧 → (𝐹‘∅)𝑥𝑧)
24	23	eximi 1817	. . . . . . . . . . . 12 ⊢ (∃𝑧 𝑠𝑥𝑧 → ∃𝑧(𝐹‘∅)𝑥𝑧)
25		peano1 7460	. . . . . . . . . . . . 13 ⊢ ∅ ∈ ω
26	2	axdclem 9790	. . . . . . . . . . . . 13 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ran 𝑥 ⊆ dom 𝑥 ∧ ∃𝑧(𝐹‘∅)𝑥𝑧) → (∅ ∈ ω → (𝐹‘∅)𝑥(𝐹‘suc ∅)))
27	25, 26	mpi 20	. . . . . . . . . . . 12 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ran 𝑥 ⊆ dom 𝑥 ∧ ∃𝑧(𝐹‘∅)𝑥𝑧) → (𝐹‘∅)𝑥(𝐹‘suc ∅))
28	24, 27	syl3an3 1158	. . . . . . . . . . 11 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ran 𝑥 ⊆ dom 𝑥 ∧ ∃𝑧 𝑠𝑥𝑧) → (𝐹‘∅)𝑥(𝐹‘suc ∅))
29	28	3com23 1119	. . . . . . . . . 10 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → (𝐹‘∅)𝑥(𝐹‘suc ∅))
30		fvex 6554	. . . . . . . . . . . . . . . . 17 ⊢ (𝐹‘𝑘) ∈ V
31		fvex 6554	. . . . . . . . . . . . . . . . 17 ⊢ (𝐹‘suc 𝑘) ∈ V
32	30, 31	brelrn 5697	. . . . . . . . . . . . . . . 16 ⊢ ((𝐹‘𝑘)𝑥(𝐹‘suc 𝑘) → (𝐹‘suc 𝑘) ∈ ran 𝑥)
33		ssel 3885	. . . . . . . . . . . . . . . 16 ⊢ (ran 𝑥 ⊆ dom 𝑥 → ((𝐹‘suc 𝑘) ∈ ran 𝑥 → (𝐹‘suc 𝑘) ∈ dom 𝑥))
34	32, 33	syl5 34	. . . . . . . . . . . . . . 15 ⊢ (ran 𝑥 ⊆ dom 𝑥 → ((𝐹‘𝑘)𝑥(𝐹‘suc 𝑘) → (𝐹‘suc 𝑘) ∈ dom 𝑥))
35	31	eldm 5658	. . . . . . . . . . . . . . 15 ⊢ ((𝐹‘suc 𝑘) ∈ dom 𝑥 ↔ ∃𝑧(𝐹‘suc 𝑘)𝑥𝑧)
36	34, 35	syl6ib 252	. . . . . . . . . . . . . 14 ⊢ (ran 𝑥 ⊆ dom 𝑥 → ((𝐹‘𝑘)𝑥(𝐹‘suc 𝑘) → ∃𝑧(𝐹‘suc 𝑘)𝑥𝑧))
37	36	ad2antll 725	. . . . . . . . . . . . 13 ⊢ ((𝑘 ∈ ω ∧ (∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ran 𝑥 ⊆ dom 𝑥)) → ((𝐹‘𝑘)𝑥(𝐹‘suc 𝑘) → ∃𝑧(𝐹‘suc 𝑘)𝑥𝑧))
38		peano2 7461	. . . . . . . . . . . . . . . . 17 ⊢ (𝑘 ∈ ω → suc 𝑘 ∈ ω)
39	2	axdclem 9790	. . . . . . . . . . . . . . . . 17 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ran 𝑥 ⊆ dom 𝑥 ∧ ∃𝑧(𝐹‘suc 𝑘)𝑥𝑧) → (suc 𝑘 ∈ ω → (𝐹‘suc 𝑘)𝑥(𝐹‘suc suc 𝑘)))
40	38, 39	syl5 34	. . . . . . . . . . . . . . . 16 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ran 𝑥 ⊆ dom 𝑥 ∧ ∃𝑧(𝐹‘suc 𝑘)𝑥𝑧) → (𝑘 ∈ ω → (𝐹‘suc 𝑘)𝑥(𝐹‘suc suc 𝑘)))
41	40	3expia 1114	. . . . . . . . . . . . . . 15 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ran 𝑥 ⊆ dom 𝑥) → (∃𝑧(𝐹‘suc 𝑘)𝑥𝑧 → (𝑘 ∈ ω → (𝐹‘suc 𝑘)𝑥(𝐹‘suc suc 𝑘))))
42	41	com3r 87	. . . . . . . . . . . . . 14 ⊢ (𝑘 ∈ ω → ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ran 𝑥 ⊆ dom 𝑥) → (∃𝑧(𝐹‘suc 𝑘)𝑥𝑧 → (𝐹‘suc 𝑘)𝑥(𝐹‘suc suc 𝑘))))
43	42	imp 407	. . . . . . . . . . . . 13 ⊢ ((𝑘 ∈ ω ∧ (∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ran 𝑥 ⊆ dom 𝑥)) → (∃𝑧(𝐹‘suc 𝑘)𝑥𝑧 → (𝐹‘suc 𝑘)𝑥(𝐹‘suc suc 𝑘)))
44	37, 43	syld 47	. . . . . . . . . . . 12 ⊢ ((𝑘 ∈ ω ∧ (∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ran 𝑥 ⊆ dom 𝑥)) → ((𝐹‘𝑘)𝑥(𝐹‘suc 𝑘) → (𝐹‘suc 𝑘)𝑥(𝐹‘suc suc 𝑘)))
45	44	3adantr2 1163	. . . . . . . . . . 11 ⊢ ((𝑘 ∈ ω ∧ (∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥)) → ((𝐹‘𝑘)𝑥(𝐹‘suc 𝑘) → (𝐹‘suc 𝑘)𝑥(𝐹‘suc suc 𝑘)))
46	45	ex 413	. . . . . . . . . 10 ⊢ (𝑘 ∈ ω → ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → ((𝐹‘𝑘)𝑥(𝐹‘suc 𝑘) → (𝐹‘suc 𝑘)𝑥(𝐹‘suc suc 𝑘))))
47	9, 13, 17, 29, 46	finds2 7469	. . . . . . . . 9 ⊢ (𝑛 ∈ ω → ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → (𝐹‘𝑛)𝑥(𝐹‘suc 𝑛)))
48	47	com12 32	. . . . . . . 8 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → (𝑛 ∈ ω → (𝐹‘𝑛)𝑥(𝐹‘suc 𝑛)))
49		fvex 6554	. . . . . . . . 9 ⊢ (𝐹‘𝑛) ∈ V
50		fvex 6554	. . . . . . . . 9 ⊢ (𝐹‘suc 𝑛) ∈ V
51	49, 50	breldm 5666	. . . . . . . 8 ⊢ ((𝐹‘𝑛)𝑥(𝐹‘suc 𝑛) → (𝐹‘𝑛) ∈ dom 𝑥)
52	48, 51	syl6 35	. . . . . . 7 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → (𝑛 ∈ ω → (𝐹‘𝑛) ∈ dom 𝑥))
53	52	ralrimiv 3147	. . . . . 6 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → ∀𝑛 ∈ ω (𝐹‘𝑛) ∈ dom 𝑥)
54		ffnfv 6748	. . . . . 6 ⊢ (𝐹:ω⟶dom 𝑥 ↔ (𝐹 Fn ω ∧ ∀𝑛 ∈ ω (𝐹‘𝑛) ∈ dom 𝑥))
55	5, 53, 54	sylanbrc 583	. . . . 5 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → 𝐹:ω⟶dom 𝑥)
56		omex 8955	. . . . . 6 ⊢ ω ∈ V
57	56	a1i 11	. . . . 5 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → ω ∈ V)
58		vex 3439	. . . . . . 7 ⊢ 𝑥 ∈ V
59	58	dmex 7475	. . . . . 6 ⊢ dom 𝑥 ∈ V
60	59	a1i 11	. . . . 5 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → dom 𝑥 ∈ V)
61		fex2 7497	. . . . 5 ⊢ ((𝐹:ω⟶dom 𝑥 ∧ ω ∈ V ∧ dom 𝑥 ∈ V) → 𝐹 ∈ V)
62	55, 57, 60, 61	syl3anc 1364	. . . 4 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → 𝐹 ∈ V)
63	48	ralrimiv 3147	. . . 4 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → ∀𝑛 ∈ ω (𝐹‘𝑛)𝑥(𝐹‘suc 𝑛))
64		fveq1 6540	. . . . . 6 ⊢ (𝑓 = 𝐹 → (𝑓‘𝑛) = (𝐹‘𝑛))
65		fveq1 6540	. . . . . 6 ⊢ (𝑓 = 𝐹 → (𝑓‘suc 𝑛) = (𝐹‘suc 𝑛))
66	64, 65	breq12d 4977	. . . . 5 ⊢ (𝑓 = 𝐹 → ((𝑓‘𝑛)𝑥(𝑓‘suc 𝑛) ↔ (𝐹‘𝑛)𝑥(𝐹‘suc 𝑛)))
67	66	ralbidv 3163	. . . 4 ⊢ (𝑓 = 𝐹 → (∀𝑛 ∈ ω (𝑓‘𝑛)𝑥(𝑓‘suc 𝑛) ↔ ∀𝑛 ∈ ω (𝐹‘𝑛)𝑥(𝐹‘suc 𝑛)))
68	62, 63, 67	elabd 3605	. . 3 ⊢ ((∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) ∧ ∃𝑧 𝑠𝑥𝑧 ∧ ran 𝑥 ⊆ dom 𝑥) → ∃𝑓∀𝑛 ∈ ω (𝑓‘𝑛)𝑥(𝑓‘suc 𝑛))
69	68	3exp 1112	. 2 ⊢ (∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦) → (∃𝑧 𝑠𝑥𝑧 → (ran 𝑥 ⊆ dom 𝑥 → ∃𝑓∀𝑛 ∈ ω (𝑓‘𝑛)𝑥(𝑓‘suc 𝑛))))
70	59	pwex 5175	. . 3 ⊢ 𝒫 dom 𝑥 ∈ V
71	70	ac4c 9747	. 2 ⊢ ∃𝑔∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≠ ∅ → (𝑔‘𝑦) ∈ 𝑦)
72	69, 71	exlimiiv 1910	1 ⊢ (∃𝑧 𝑠𝑥𝑧 → (ran 𝑥 ⊆ dom 𝑥 → ∃𝑓∀𝑛 ∈ ω (𝑓‘𝑛)𝑥(𝑓‘suc 𝑛)))

Syntax hints:   → wi 4   ∧ wa 396   ∧ w3a 1080   = wceq 1522  ∃wex 1762   ∈ wcel 2080  {cab 2774   ≠ wne 2983  ∀wral 3104  Vcvv 3436   ⊆ wss 3861  ∅c0 4213  𝒫 cpw 4455   class class class wbr 4964   ↦ cmpt 5043  dom cdm 5446  ran crn 5447   ↾ cres 5448  suc csuc 6071   Fn wfn 6223  ⟶wf 6224  ‘cfv 6228  ωcom 7439  reccrdg 7900

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1778  ax-4 1792  ax-5 1889  ax-6 1948  ax-7 1993  ax-8 2082  ax-9 2090  ax-10 2111  ax-11 2125  ax-12 2140  ax-13 2343  ax-ext 2768  ax-rep 5084  ax-sep 5097  ax-nul 5104  ax-pow 5160  ax-pr 5224  ax-un 7322  ax-inf2 8953  ax-ac2 9734

This theorem depends on definitions:  df-bi 208  df-an 397  df-or 843  df-3or 1081  df-3an 1082  df-tru 1525  df-ex 1763  df-nf 1767  df-sb 2042  df-mo 2575  df-eu 2611  df-clab 2775  df-cleq 2787  df-clel 2862  df-nfc 2934  df-ne 2984  df-ral 3109  df-rex 3110  df-reu 3111  df-rab 3113  df-v 3438  df-sbc 3708  df-csb 3814  df-dif 3864  df-un 3866  df-in 3868  df-ss 3876  df-pss 3878  df-nul 4214  df-if 4384  df-pw 4457  df-sn 4475  df-pr 4477  df-tp 4479  df-op 4481  df-uni 4748  df-iun 4829  df-br 4965  df-opab 5027  df-mpt 5044  df-tr 5067  df-id 5351  df-eprel 5356  df-po 5365  df-so 5366  df-fr 5405  df-we 5407  df-xp 5452  df-rel 5453  df-cnv 5454  df-co 5455  df-dm 5456  df-rn 5457  df-res 5458  df-ima 5459  df-pred 6026  df-ord 6072  df-on 6073  df-lim 6074  df-suc 6075  df-iota 6192  df-fun 6230  df-fn 6231  df-f 6232  df-f1 6233  df-fo 6234  df-f1o 6235  df-fv 6236  df-om 7440  df-wrecs 7801  df-recs 7863  df-rdg 7901  df-ac 9391

This theorem is referenced by:  axdc  9792