Theorem f1ocnt 28946

Description: Given a countable set 𝐴, number its elements by providing a one-to-one mapping either with ℕ or an integer range starting from 1. The domain of the function can then be used with iundisjcnt 28944 or iundisj2cnt 28945. (Contributed by Thierry Arnoux, 25-Jul-2020.)

Assertion

Ref	Expression
f1ocnt	⊢ (𝐴 ≼ ω → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))

Distinct variable group:   𝐴,𝑓

Proof of Theorem f1ocnt

Dummy variable 𝑔 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		f1o0 6085	. . . . . . 7 ⊢ ∅:∅–1-1-onto→∅
2		eqidd 2611	. . . . . . . 8 ⊢ (𝐴 = ∅ → ∅ = ∅)
3		dm0 5260	. . . . . . . . 9 ⊢ dom ∅ = ∅
4	3	a1i 11	. . . . . . . 8 ⊢ (𝐴 = ∅ → dom ∅ = ∅)
5		id 22	. . . . . . . 8 ⊢ (𝐴 = ∅ → 𝐴 = ∅)
6	2, 4, 5	f1oeq123d 6046	. . . . . . 7 ⊢ (𝐴 = ∅ → (∅:dom ∅–1-1-onto→𝐴 ↔ ∅:∅–1-1-onto→∅))
7	1, 6	mpbiri 247	. . . . . 6 ⊢ (𝐴 = ∅ → ∅:dom ∅–1-1-onto→𝐴)
8		fveq2 6103	. . . . . . . . . . . . 13 ⊢ (𝐴 = ∅ → (#‘𝐴) = (#‘∅))
9		hash0 13019	. . . . . . . . . . . . 13 ⊢ (#‘∅) = 0
10	8, 9	syl6eq 2660	. . . . . . . . . . . 12 ⊢ (𝐴 = ∅ → (#‘𝐴) = 0)
11	10	oveq1d 6564	. . . . . . . . . . 11 ⊢ (𝐴 = ∅ → ((#‘𝐴) + 1) = (0 + 1))
12		0p1e1 11009	. . . . . . . . . . 11 ⊢ (0 + 1) = 1
13	11, 12	syl6eq 2660	. . . . . . . . . 10 ⊢ (𝐴 = ∅ → ((#‘𝐴) + 1) = 1)
14	13	oveq2d 6565	. . . . . . . . 9 ⊢ (𝐴 = ∅ → (1..^((#‘𝐴) + 1)) = (1..^1))
15		fzo0 12361	. . . . . . . . 9 ⊢ (1..^1) = ∅
16	14, 15	syl6eq 2660	. . . . . . . 8 ⊢ (𝐴 = ∅ → (1..^((#‘𝐴) + 1)) = ∅)
17	4, 16	eqtr4d 2647	. . . . . . 7 ⊢ (𝐴 = ∅ → dom ∅ = (1..^((#‘𝐴) + 1)))
18	17	olcd 407	. . . . . 6 ⊢ (𝐴 = ∅ → (dom ∅ = ℕ ∨ dom ∅ = (1..^((#‘𝐴) + 1))))
19	7, 18	jca 553	. . . . 5 ⊢ (𝐴 = ∅ → (∅:dom ∅–1-1-onto→𝐴 ∧ (dom ∅ = ℕ ∨ dom ∅ = (1..^((#‘𝐴) + 1)))))
20		0ex 4718	. . . . . 6 ⊢ ∅ ∈ V
21		id 22	. . . . . . . 8 ⊢ (𝑓 = ∅ → 𝑓 = ∅)
22		dmeq 5246	. . . . . . . 8 ⊢ (𝑓 = ∅ → dom 𝑓 = dom ∅)
23		eqidd 2611	. . . . . . . 8 ⊢ (𝑓 = ∅ → 𝐴 = 𝐴)
24	21, 22, 23	f1oeq123d 6046	. . . . . . 7 ⊢ (𝑓 = ∅ → (𝑓:dom 𝑓–1-1-onto→𝐴 ↔ ∅:dom ∅–1-1-onto→𝐴))
25	22	eqeq1d 2612	. . . . . . . 8 ⊢ (𝑓 = ∅ → (dom 𝑓 = ℕ ↔ dom ∅ = ℕ))
26	22	eqeq1d 2612	. . . . . . . 8 ⊢ (𝑓 = ∅ → (dom 𝑓 = (1..^((#‘𝐴) + 1)) ↔ dom ∅ = (1..^((#‘𝐴) + 1))))
27	25, 26	orbi12d 742	. . . . . . 7 ⊢ (𝑓 = ∅ → ((dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1))) ↔ (dom ∅ = ℕ ∨ dom ∅ = (1..^((#‘𝐴) + 1)))))
28	24, 27	anbi12d 743	. . . . . 6 ⊢ (𝑓 = ∅ → ((𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))) ↔ (∅:dom ∅–1-1-onto→𝐴 ∧ (dom ∅ = ℕ ∨ dom ∅ = (1..^((#‘𝐴) + 1))))))
29	20, 28	spcev 3273	. . . . 5 ⊢ ((∅:dom ∅–1-1-onto→𝐴 ∧ (dom ∅ = ℕ ∨ dom ∅ = (1..^((#‘𝐴) + 1)))) → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))
30	19, 29	syl 17	. . . 4 ⊢ (𝐴 = ∅ → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))
31	30	adantl 481	. . 3 ⊢ (((𝐴 ≼ ω ∧ 𝐴 ∈ Fin) ∧ 𝐴 = ∅) → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))
32		f1odm 6054	. . . . . . . . . . 11 ⊢ (𝑓:(1...(#‘𝐴))–1-1-onto→𝐴 → dom 𝑓 = (1...(#‘𝐴)))
33		f1oeq2 6041	. . . . . . . . . . 11 ⊢ (dom 𝑓 = (1...(#‘𝐴)) → (𝑓:dom 𝑓–1-1-onto→𝐴 ↔ 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴))
34	32, 33	syl 17	. . . . . . . . . 10 ⊢ (𝑓:(1...(#‘𝐴))–1-1-onto→𝐴 → (𝑓:dom 𝑓–1-1-onto→𝐴 ↔ 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴))
35	34	ibir 256	. . . . . . . . 9 ⊢ (𝑓:(1...(#‘𝐴))–1-1-onto→𝐴 → 𝑓:dom 𝑓–1-1-onto→𝐴)
36	35	adantl 481	. . . . . . . 8 ⊢ (((#‘𝐴) ∈ ℕ ∧ 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴) → 𝑓:dom 𝑓–1-1-onto→𝐴)
37	32	adantl 481	. . . . . . . . . 10 ⊢ (((#‘𝐴) ∈ ℕ ∧ 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴) → dom 𝑓 = (1...(#‘𝐴)))
38		simpl 472	. . . . . . . . . . . 12 ⊢ (((#‘𝐴) ∈ ℕ ∧ 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴) → (#‘𝐴) ∈ ℕ)
39	38	nnzd 11357	. . . . . . . . . . 11 ⊢ (((#‘𝐴) ∈ ℕ ∧ 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴) → (#‘𝐴) ∈ ℤ)
40		fzval3 12404	. . . . . . . . . . 11 ⊢ ((#‘𝐴) ∈ ℤ → (1...(#‘𝐴)) = (1..^((#‘𝐴) + 1)))
41	39, 40	syl 17	. . . . . . . . . 10 ⊢ (((#‘𝐴) ∈ ℕ ∧ 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴) → (1...(#‘𝐴)) = (1..^((#‘𝐴) + 1)))
42	37, 41	eqtrd 2644	. . . . . . . . 9 ⊢ (((#‘𝐴) ∈ ℕ ∧ 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴) → dom 𝑓 = (1..^((#‘𝐴) + 1)))
43	42	olcd 407	. . . . . . . 8 ⊢ (((#‘𝐴) ∈ ℕ ∧ 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴) → (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1))))
44	36, 43	jca 553	. . . . . . 7 ⊢ (((#‘𝐴) ∈ ℕ ∧ 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴) → (𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))
45	44	ex 449	. . . . . 6 ⊢ ((#‘𝐴) ∈ ℕ → (𝑓:(1...(#‘𝐴))–1-1-onto→𝐴 → (𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1))))))
46	45	eximdv 1833	. . . . 5 ⊢ ((#‘𝐴) ∈ ℕ → (∃𝑓 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴 → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1))))))
47	46	imp 444	. . . 4 ⊢ (((#‘𝐴) ∈ ℕ ∧ ∃𝑓 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴) → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))
48	47	adantl 481	. . 3 ⊢ (((𝐴 ≼ ω ∧ 𝐴 ∈ Fin) ∧ ((#‘𝐴) ∈ ℕ ∧ ∃𝑓 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴)) → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))
49		fz1f1o 14288	. . . 4 ⊢ (𝐴 ∈ Fin → (𝐴 = ∅ ∨ ((#‘𝐴) ∈ ℕ ∧ ∃𝑓 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴)))
50	49	adantl 481	. . 3 ⊢ ((𝐴 ≼ ω ∧ 𝐴 ∈ Fin) → (𝐴 = ∅ ∨ ((#‘𝐴) ∈ ℕ ∧ ∃𝑓 𝑓:(1...(#‘𝐴))–1-1-onto→𝐴)))
51	31, 48, 50	mpjaodan 823	. 2 ⊢ ((𝐴 ≼ ω ∧ 𝐴 ∈ Fin) → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))
52		isfinite 8432	. . . . . . . . . 10 ⊢ (𝐴 ∈ Fin ↔ 𝐴 ≺ ω)
53	52	notbii 309	. . . . . . . . 9 ⊢ (¬ 𝐴 ∈ Fin ↔ ¬ 𝐴 ≺ ω)
54	53	biimpi 205	. . . . . . . 8 ⊢ (¬ 𝐴 ∈ Fin → ¬ 𝐴 ≺ ω)
55	54	anim2i 591	. . . . . . 7 ⊢ ((𝐴 ≼ ω ∧ ¬ 𝐴 ∈ Fin) → (𝐴 ≼ ω ∧ ¬ 𝐴 ≺ ω))
56		bren2 7872	. . . . . . 7 ⊢ (𝐴 ≈ ω ↔ (𝐴 ≼ ω ∧ ¬ 𝐴 ≺ ω))
57	55, 56	sylibr 223	. . . . . 6 ⊢ ((𝐴 ≼ ω ∧ ¬ 𝐴 ∈ Fin) → 𝐴 ≈ ω)
58		nnenom 12641	. . . . . . 7 ⊢ ℕ ≈ ω
59	58	ensymi 7892	. . . . . 6 ⊢ ω ≈ ℕ
60		entr 7894	. . . . . 6 ⊢ ((𝐴 ≈ ω ∧ ω ≈ ℕ) → 𝐴 ≈ ℕ)
61	57, 59, 60	sylancl 693	. . . . 5 ⊢ ((𝐴 ≼ ω ∧ ¬ 𝐴 ∈ Fin) → 𝐴 ≈ ℕ)
62		bren 7850	. . . . 5 ⊢ (𝐴 ≈ ℕ ↔ ∃𝑔 𝑔:𝐴–1-1-onto→ℕ)
63	61, 62	sylib 207	. . . 4 ⊢ ((𝐴 ≼ ω ∧ ¬ 𝐴 ∈ Fin) → ∃𝑔 𝑔:𝐴–1-1-onto→ℕ)
64		f1oexbi 7009	. . . 4 ⊢ (∃𝑔 𝑔:𝐴–1-1-onto→ℕ ↔ ∃𝑓 𝑓:ℕ–1-1-onto→𝐴)
65	63, 64	sylib 207	. . 3 ⊢ ((𝐴 ≼ ω ∧ ¬ 𝐴 ∈ Fin) → ∃𝑓 𝑓:ℕ–1-1-onto→𝐴)
66		f1odm 6054	. . . . . . 7 ⊢ (𝑓:ℕ–1-1-onto→𝐴 → dom 𝑓 = ℕ)
67		f1oeq2 6041	. . . . . . 7 ⊢ (dom 𝑓 = ℕ → (𝑓:dom 𝑓–1-1-onto→𝐴 ↔ 𝑓:ℕ–1-1-onto→𝐴))
68	66, 67	syl 17	. . . . . 6 ⊢ (𝑓:ℕ–1-1-onto→𝐴 → (𝑓:dom 𝑓–1-1-onto→𝐴 ↔ 𝑓:ℕ–1-1-onto→𝐴))
69	68	ibir 256	. . . . 5 ⊢ (𝑓:ℕ–1-1-onto→𝐴 → 𝑓:dom 𝑓–1-1-onto→𝐴)
70	66	orcd 406	. . . . 5 ⊢ (𝑓:ℕ–1-1-onto→𝐴 → (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1))))
71	69, 70	jca 553	. . . 4 ⊢ (𝑓:ℕ–1-1-onto→𝐴 → (𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))
72	71	eximi 1752	. . 3 ⊢ (∃𝑓 𝑓:ℕ–1-1-onto→𝐴 → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))
73	65, 72	syl 17	. 2 ⊢ ((𝐴 ≼ ω ∧ ¬ 𝐴 ∈ Fin) → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))
74	51, 73	pm2.61dan 828	1 ⊢ (𝐴 ≼ ω → ∃𝑓(𝑓:dom 𝑓–1-1-onto→𝐴 ∧ (dom 𝑓 = ℕ ∨ dom 𝑓 = (1..^((#‘𝐴) + 1)))))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 195   ∨ wo 382   ∧ wa 383   = wceq 1475  ∃wex 1695   ∈ wcel 1977  ∅c0 3874   class class class wbr 4583  dom cdm 5038  –1-1-onto→wf1o 5803  ‘cfv 5804  (class class class)co 6549  ωcom 6957   ≈ cen 7838   ≼ cdom 7839   ≺ csdm 7840  Fincfn 7841  0cc0 9815  1c1 9816   + caddc 9818  ℕcn 10897  ℤcz 11254  ...cfz 12197  ..^cfzo 12334  #chash 12979

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-8 1979  ax-9 1986  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590  ax-sep 4709  ax-nul 4717  ax-pow 4769  ax-pr 4833  ax-un 6847  ax-inf2 8421  ax-cnex 9871  ax-resscn 9872  ax-1cn 9873  ax-icn 9874  ax-addcl 9875  ax-addrcl 9876  ax-mulcl 9877  ax-mulrcl 9878  ax-mulcom 9879  ax-addass 9880  ax-mulass 9881  ax-distr 9882  ax-i2m1 9883  ax-1ne0 9884  ax-1rid 9885  ax-rnegex 9886  ax-rrecex 9887  ax-cnre 9888  ax-pre-lttri 9889  ax-pre-lttrn 9890  ax-pre-ltadd 9891  ax-pre-mulgt0 9892

This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3or 1032  df-3an 1033  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-eu 2462  df-mo 2463  df-clab 2597  df-cleq 2603  df-clel 2606  df-nfc 2740  df-ne 2782  df-nel 2783  df-ral 2901  df-rex 2902  df-reu 2903  df-rab 2905  df-v 3175  df-sbc 3403  df-csb 3500  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-pss 3556  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-tp 4130  df-op 4132  df-uni 4373  df-int 4411  df-iun 4457  df-br 4584  df-opab 4644  df-mpt 4645  df-tr 4681  df-eprel 4949  df-id 4953  df-po 4959  df-so 4960  df-fr 4997  df-we 4999  df-xp 5044  df-rel 5045  df-cnv 5046  df-co 5047  df-dm 5048  df-rn 5049  df-res 5050  df-ima 5051  df-pred 5597  df-ord 5643  df-on 5644  df-lim 5645  df-suc 5646  df-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-fv 5812  df-riota 6511  df-ov 6552  df-oprab 6553  df-mpt2 6554  df-om 6958  df-1st 7059  df-2nd 7060  df-wrecs 7294  df-recs 7355  df-rdg 7393  df-1o 7447  df-er 7629  df-en 7842  df-dom 7843  df-sdom 7844  df-fin 7845  df-card 8648  df-pnf 9955  df-mnf 9956  df-xr 9957  df-ltxr 9958  df-le 9959  df-sub 10147  df-neg 10148  df-nn 10898  df-n0 11170  df-z 11255  df-uz 11564  df-fz 12198  df-fzo 12335  df-hash 12980

This theorem is referenced by: (None)