Theorem hashennn 11242

Description: The size of a set equinumerous to an element of ω. (Contributed by Jim Kingdon, 21-Feb-2022.)

Assertion

Ref	Expression
hashennn	⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → (♯‘𝐴) = (frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0)‘𝑁))

Distinct variable groups:   𝑥,𝐴   𝑥,𝑁

Proof of Theorem hashennn

Dummy variables 𝑦 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-ihash 11238	. . . . 5 ⊢ ♯ = ((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩}) ∘ (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}))
2	1	fveq1i 5699	. . . 4 ⊢ (♯‘𝐴) = (((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩}) ∘ (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}))‘𝐴)
3		funmpt 5418	. . . . 5 ⊢ Fun (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})
4		hashennnuni 11241	. . . . . . . . 9 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴} = 𝑁)
5	4	eqcomd 2244	. . . . . . . 8 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → 𝑁 = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴})
6		nnfi 7179	. . . . . . . . . . 11 ⊢ (𝑁 ∈ ω → 𝑁 ∈ Fin)
7	6	adantr 276	. . . . . . . . . 10 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → 𝑁 ∈ Fin)
8		simpr 110	. . . . . . . . . . 11 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → 𝑁 ≈ 𝐴)
9	8	ensymd 7075	. . . . . . . . . 10 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → 𝐴 ≈ 𝑁)
10		enfii 7181	. . . . . . . . . 10 ⊢ ((𝑁 ∈ Fin ∧ 𝐴 ≈ 𝑁) → 𝐴 ∈ Fin)
11	7, 9, 10	syl2anc 415	. . . . . . . . 9 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → 𝐴 ∈ Fin)
12		simpl 109	. . . . . . . . 9 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → 𝑁 ∈ ω)
13		simpr 110	. . . . . . . . . . 11 ⊢ ((𝑥 = 𝐴 ∧ 𝑧 = 𝑁) → 𝑧 = 𝑁)
14		breq2 4135	. . . . . . . . . . . . . 14 ⊢ (𝑥 = 𝐴 → (𝑦 ≼ 𝑥 ↔ 𝑦 ≼ 𝐴))
15	14	adantr 276	. . . . . . . . . . . . 13 ⊢ ((𝑥 = 𝐴 ∧ 𝑧 = 𝑁) → (𝑦 ≼ 𝑥 ↔ 𝑦 ≼ 𝐴))
16	15	rabbidv 2810	. . . . . . . . . . . 12 ⊢ ((𝑥 = 𝐴 ∧ 𝑧 = 𝑁) → {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥} = {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴})
17	16	unieqd 3946	. . . . . . . . . . 11 ⊢ ((𝑥 = 𝐴 ∧ 𝑧 = 𝑁) → ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥} = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴})
18	13, 17	eqeq12d 2253	. . . . . . . . . 10 ⊢ ((𝑥 = 𝐴 ∧ 𝑧 = 𝑁) → (𝑧 = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥} ↔ 𝑁 = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴}))
19	18	opelopabga 4407	. . . . . . . . 9 ⊢ ((𝐴 ∈ Fin ∧ 𝑁 ∈ ω) → (⟨𝐴, 𝑁⟩ ∈ {⟨𝑥, 𝑧⟩ ∣ 𝑧 = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}} ↔ 𝑁 = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴}))
20	11, 12, 19	syl2anc 415	. . . . . . . 8 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → (⟨𝐴, 𝑁⟩ ∈ {⟨𝑥, 𝑧⟩ ∣ 𝑧 = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}} ↔ 𝑁 = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴}))
21	5, 20	mpbird 167	. . . . . . 7 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → ⟨𝐴, 𝑁⟩ ∈ {⟨𝑥, 𝑧⟩ ∣ 𝑧 = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}})
22		mptv 4230	. . . . . . 7 ⊢ (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}) = {⟨𝑥, 𝑧⟩ ∣ 𝑧 = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}}
23	21, 22	eleqtrrdi 2332	. . . . . 6 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → ⟨𝐴, 𝑁⟩ ∈ (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}))
24		opeldmg 4988	. . . . . . 7 ⊢ ((𝐴 ∈ Fin ∧ 𝑁 ∈ ω) → (⟨𝐴, 𝑁⟩ ∈ (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}) → 𝐴 ∈ dom (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})))
25	11, 12, 24	syl2anc 415	. . . . . 6 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → (⟨𝐴, 𝑁⟩ ∈ (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}) → 𝐴 ∈ dom (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})))
26	23, 25	mpd 13	. . . . 5 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → 𝐴 ∈ dom (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}))
27		fvco 5778	. . . . 5 ⊢ ((Fun (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}) ∧ 𝐴 ∈ dom (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})) → (((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩}) ∘ (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}))‘𝐴) = ((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩})‘((𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})‘𝐴)))
28	3, 26, 27	sylancr 418	. . . 4 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → (((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩}) ∘ (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}))‘𝐴) = ((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩})‘((𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})‘𝐴)))
29	2, 28	eqtrid 2283	. . 3 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → (♯‘𝐴) = ((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩})‘((𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})‘𝐴)))
30	11	elexd 2835	. . . . . 6 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → 𝐴 ∈ V)
31	4, 12	eqeltrd 2315	. . . . . 6 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴} ∈ ω)
32	14	rabbidv 2810	. . . . . . . 8 ⊢ (𝑥 = 𝐴 → {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥} = {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴})
33	32	unieqd 3946	. . . . . . 7 ⊢ (𝑥 = 𝐴 → ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥} = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴})
34		eqid 2238	. . . . . . 7 ⊢ (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥}) = (𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})
35	33, 34	fvmptg 5784	. . . . . 6 ⊢ ((𝐴 ∈ V ∧ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴} ∈ ω) → ((𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})‘𝐴) = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴})
36	30, 31, 35	syl2anc 415	. . . . 5 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → ((𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})‘𝐴) = ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝐴})
37	36, 4	eqtrd 2271	. . . 4 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → ((𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})‘𝐴) = 𝑁)
38	37	fveq2d 5702	. . 3 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → ((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩})‘((𝑥 ∈ V ↦ ∪ {𝑦 ∈ (ω ∪ {ω}) ∣ 𝑦 ≼ 𝑥})‘𝐴)) = ((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩})‘𝑁))
39	29, 38	eqtrd 2271	. 2 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → (♯‘𝐴) = ((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩})‘𝑁))
40		ordom 4756	. . . . . . 7 ⊢ Ord ω
41		ordirr 4691	. . . . . . 7 ⊢ (Ord ω → ¬ ω ∈ ω)
42	40, 41	ax-mp 5	. . . . . 6 ⊢ ¬ ω ∈ ω
43		eleq1 2301	. . . . . 6 ⊢ (ω = 𝑁 → (ω ∈ ω ↔ 𝑁 ∈ ω))
44	42, 43	mtbii 685	. . . . 5 ⊢ (ω = 𝑁 → ¬ 𝑁 ∈ ω)
45	44	necon2ai 2474	. . . 4 ⊢ (𝑁 ∈ ω → ω ≠ 𝑁)
46		fvunsng 5912	. . . 4 ⊢ ((𝑁 ∈ ω ∧ ω ≠ 𝑁) → ((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩})‘𝑁) = (frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0)‘𝑁))
47	45, 46	mpdan 425	. . 3 ⊢ (𝑁 ∈ ω → ((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩})‘𝑁) = (frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0)‘𝑁))
48	47	adantr 276	. 2 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → ((frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0) ∪ {⟨ω, +∞⟩})‘𝑁) = (frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0)‘𝑁))
49	39, 48	eqtrd 2271	1 ⊢ ((𝑁 ∈ ω ∧ 𝑁 ≈ 𝐴) → (♯‘𝐴) = (frec((𝑥 ∈ ℤ ↦ (𝑥 + 1)), 0)‘𝑁))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ∧ wa 104   ↔ wb 105   = wceq 1402   ∈ wcel 2209   ≠ wne 2420  {crab 2532  Vcvv 2821   ∪ cun 3218  {csn 3709  ⟨cop 3712  ∪ cuni 3935   class class class wbr 4131  {copab 4192   ↦ cmpt 4193  Ord word 4509  ωcom 4739  dom cdm 4776   ∘ ccom 4780  Fun wfun 5374  ‘cfv 5380  (class class class)co 6088  freccfrec 6665   ≈ cen 7025   ≼ cdom 7026  Fincfn 7027  0cc0 8186  1c1 8187   + caddc 8189  +∞cpnf 8364  ℤcz 9656  ♯chash 11237

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4251  ax-nul 4261  ax-pow 4313  ax-pr 4348  ax-un 4580  ax-setind 4686  ax-iinf 4737

This proof depends on definitions:  df-bi 117  df-dc 847  df-3or 1010  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-ral 2533  df-rex 2534  df-rab 2537  df-v 2823  df-sbc 3052  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-int 3971  df-br 4132  df-opab 4194  df-mpt 4195  df-tr 4232  df-id 4440  df-iord 4513  df-on 4515  df-suc 4518  df-iom 4740  df-xp 4782  df-rel 4783  df-cnv 4784  df-co 4785  df-dm 4786  df-rn 4787  df-res 4788  df-ima 4789  df-iota 5340  df-fun 5382  df-fn 5383  df-f 5384  df-f1 5385  df-fo 5386  df-f1o 5387  df-fv 5388  df-er 6811  df-en 7028  df-dom 7029  df-fin 7030  df-ihash 11238

This theorem is used by:  hashcl  11243  hashfz1  11245  hashen  11246  fihashdom  11266  hashun  11268