Theorem wrdl3s3 15122

Description: A word of length 3 is a length 3 string. (Contributed by AV, 18-May-2021.)

Assertion

Ref	Expression
wrdl3s3	⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) ↔ ∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩)

Distinct variable groups:   𝑉,𝑎,𝑏,𝑐   𝑊,𝑎,𝑏,𝑐

Proof of Theorem wrdl3s3

Step	Hyp	Ref	Expression
1		c0ex 11305	. . . . . . . 8 ⊢ 0 ∈ V
2	1	tpid1 4725	. . . . . . 7 ⊢ 0 ∈ {0, 1, 2}
3		fzo0to3tp 13892	. . . . . . 7 ⊢ (0..^3) = {0, 1, 2}
4	2, 3	eleqtrri 2859	. . . . . 6 ⊢ 0 ∈ (0..^3)
5		oveq2 7430	. . . . . 6 ⊢ ((♯‘𝑊) = 3 → (0..^(♯‘𝑊)) = (0..^3))
6	4, 5	eleqtrrid 2867	. . . . 5 ⊢ ((♯‘𝑊) = 3 → 0 ∈ (0..^(♯‘𝑊)))
7		wrdsymbcl 14677	. . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 0 ∈ (0..^(♯‘𝑊))) → (𝑊‘0) ∈ 𝑉)
8	6, 7	sylan2 605	. . . 4 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → (𝑊‘0) ∈ 𝑉)
9		1eltp012 12418	. . . . . . 7 ⊢ 1 ∈ {0, 1, 2}
10	9, 3	eleqtrri 2859	. . . . . 6 ⊢ 1 ∈ (0..^3)
11	10, 5	eleqtrrid 2867	. . . . 5 ⊢ ((♯‘𝑊) = 3 → 1 ∈ (0..^(♯‘𝑊)))
12		wrdsymbcl 14677	. . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 1 ∈ (0..^(♯‘𝑊))) → (𝑊‘1) ∈ 𝑉)
13	11, 12	sylan2 605	. . . 4 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → (𝑊‘1) ∈ 𝑉)
14		2ex 12425	. . . . . . . 8 ⊢ 2 ∈ V
15	14	tpid3 4730	. . . . . . 7 ⊢ 2 ∈ {0, 1, 2}
16	15, 3	eleqtrri 2859	. . . . . 6 ⊢ 2 ∈ (0..^3)
17	16, 5	eleqtrrid 2867	. . . . 5 ⊢ ((♯‘𝑊) = 3 → 2 ∈ (0..^(♯‘𝑊)))
18		wrdsymbcl 14677	. . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 2 ∈ (0..^(♯‘𝑊))) → (𝑊‘2) ∈ 𝑉)
19	17, 18	sylan2 605	. . . 4 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → (𝑊‘2) ∈ 𝑉)
20		simpr 490	. . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → (♯‘𝑊) = 3)
21		eqid 2760	. . . . . 6 ⊢ (𝑊‘0) = (𝑊‘0)
22		eqid 2760	. . . . . 6 ⊢ (𝑊‘1) = (𝑊‘1)
23		eqid 2760	. . . . . 6 ⊢ (𝑊‘2) = (𝑊‘2)
24	21, 22, 23	3pm3.2i 1358	. . . . 5 ⊢ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = (𝑊‘2))
25	20, 24	jctir 530	. . . 4 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = (𝑊‘2))))
26		eqeq2 2772	. . . . . . 7 ⊢ (𝑎 = (𝑊‘0) → ((𝑊‘0) = 𝑎 ↔ (𝑊‘0) = (𝑊‘0)))
27	26	3anbi1d 1468	. . . . . 6 ⊢ (𝑎 = (𝑊‘0) → (((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐) ↔ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)))
28	27	anbi2d 642	. . . . 5 ⊢ (𝑎 = (𝑊‘0) → (((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)) ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐))))
29		eqeq2 2772	. . . . . . 7 ⊢ (𝑏 = (𝑊‘1) → ((𝑊‘1) = 𝑏 ↔ (𝑊‘1) = (𝑊‘1)))
30	29	3anbi2d 1469	. . . . . 6 ⊢ (𝑏 = (𝑊‘1) → (((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐) ↔ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = 𝑐)))
31	30	anbi2d 642	. . . . 5 ⊢ (𝑏 = (𝑊‘1) → (((♯‘𝑊) = 3 ∧ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)) ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = 𝑐))))
32		eqeq2 2772	. . . . . . 7 ⊢ (𝑐 = (𝑊‘2) → ((𝑊‘2) = 𝑐 ↔ (𝑊‘2) = (𝑊‘2)))
33	32	3anbi3d 1470	. . . . . 6 ⊢ (𝑐 = (𝑊‘2) → (((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = 𝑐) ↔ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = (𝑊‘2))))
34	33	anbi2d 642	. . . . 5 ⊢ (𝑐 = (𝑊‘2) → (((♯‘𝑊) = 3 ∧ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = 𝑐)) ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = (𝑊‘2)))))
35	28, 31, 34	rspc3ev 3592	. . . 4 ⊢ ((((𝑊‘0) ∈ 𝑉 ∧ (𝑊‘1) ∈ 𝑉 ∧ (𝑊‘2) ∈ 𝑉) ∧ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = (𝑊‘2)))) → ∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)))
36	8, 13, 19, 25, 35	syl31anc 1400	. . 3 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → ∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)))
37		df-3an 1105	. . . . . . . . 9 ⊢ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉 ∧ 𝑐 ∈ 𝑉) ↔ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉))
38		eqwrds3 15121	. . . . . . . . . 10 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉 ∧ 𝑐 ∈ 𝑉)) → (𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐))))
39	38	ex 418	. . . . . . . . 9 ⊢ (𝑊 ∈ Word 𝑉 → ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉 ∧ 𝑐 ∈ 𝑉) → (𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)))))
40	37, 39	biimtrrid 246	. . . . . . . 8 ⊢ (𝑊 ∈ Word 𝑉 → (((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) → (𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)))))
41	40	expd 421	. . . . . . 7 ⊢ (𝑊 ∈ Word 𝑉 → ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → (𝑐 ∈ 𝑉 → (𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐))))))
42	41	adantr 486	. . . . . 6 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → (𝑐 ∈ 𝑉 → (𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐))))))
43	42	imp31 423	. . . . 5 ⊢ ((((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) ∧ 𝑐 ∈ 𝑉) → (𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐))))
44	43	rexbidva 3184	. . . 4 ⊢ (((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) → (∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ∃𝑐 ∈ 𝑉 ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐))))
45	44	2rexbidva 3225	. . 3 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → (∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐))))
46	36, 45	mpbird 260	. 2 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → ∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩)
47		s3cl 15036	. . . . . . 7 ⊢ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉 ∧ 𝑐 ∈ 𝑉) → ⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉)
48	47	ad4ant123 1191	. . . . . 6 ⊢ ((((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) ∧ 𝑊 = ⟨“𝑎𝑏𝑐”⟩) → ⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉)
49		s3len 15052	. . . . . 6 ⊢ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3
50	48, 49	jctir 530	. . . . 5 ⊢ ((((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) ∧ 𝑊 = ⟨“𝑎𝑏𝑐”⟩) → (⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉 ∧ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3))
51		eleq1 2848	. . . . . . 7 ⊢ (𝑊 = ⟨“𝑎𝑏𝑐”⟩ → (𝑊 ∈ Word 𝑉 ↔ ⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉))
52		fveqeq2 6897	. . . . . . 7 ⊢ (𝑊 = ⟨“𝑎𝑏𝑐”⟩ → ((♯‘𝑊) = 3 ↔ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3))
53	51, 52	anbi12d 644	. . . . . 6 ⊢ (𝑊 = ⟨“𝑎𝑏𝑐”⟩ → ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) ↔ (⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉 ∧ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3)))
54	53	adantl 487	. . . . 5 ⊢ ((((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) ∧ 𝑊 = ⟨“𝑎𝑏𝑐”⟩) → ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) ↔ (⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉 ∧ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3)))
55	50, 54	mpbird 260	. . . 4 ⊢ ((((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) ∧ 𝑊 = ⟨“𝑎𝑏𝑐”⟩) → (𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3))
56	55	rexlimdva2 3165	. . 3 ⊢ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → (∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩ → (𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3)))
57	56	rexlimivv 3204	. 2 ⊢ (∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩ → (𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3))
58	46, 57	impbii 212	1 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) ↔ ∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩)

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   ∧ w3a 1103   = wceq 1569   ∈ wcel 2144  ∃wrex 3086  {ctp 4588  ‘cfv 6541  (class class class)co 7422  0cc0 11205  1c1 11206  2c2 12402  3c3 12403  ..^cfzo 13793  ♯chash 14479  Word cword 14663  ⟨“cs3 14999

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-10 2177  ax-11 2193  ax-12 2212  ax-ext 2732  ax-rep 5231  ax-sep 5248  ax-nul 5259  ax-pow 5326  ax-pr 5390  ax-un 7753  ax-cnex 11261  ax-resscn 11262  ax-1cn 11263  ax-icn 11264  ax-addcl 11265  ax-addrcl 11266  ax-mulcl 11267  ax-mulrcl 11268  ax-mulcom 11269  ax-addass 11270  ax-mulass 11271  ax-distr 11272  ax-i2m1 11273  ax-1ne0 11274  ax-1rid 11275  ax-rnegex 11276  ax-rrecex 11277  ax-cnre 11278  ax-pre-lttri 11279  ax-pre-lttrn 11280  ax-pre-ltadd 11281  ax-pre-mulgt0 11282

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-nf 1816  df-sb 2099  df-mo 2564  df-eu 2594  df-clab 2739  df-cleq 2752  df-clel 2835  df-nfc 2909  df-ne 2956  df-nel 3062  df-ral 3077  df-rex 3087  df-reu 3366  df-rab 3413  df-v 3452  df-sbc 3739  df-csb 3848  df-ss 3897  df-pss 4013  df-dif 4046  df-in 4090  df-un 4150  df-nul 4278  df-if 4482  df-pw 4558  df-sn 4585  df-pr 4587  df-tp 4589  df-op 4835  df-uni 4867  df-int 4907  df-iun 4952  df-br 5103  df-opab 5167  df-mpt 5186  df-tr 5212  df-id 5545  df-eprel 5550  df-po 5558  df-so 5559  df-fr 5603  df-we 5605  df-xp 5656  df-rel 5657  df-cnv 5658  df-co 5659  df-dm 5660  df-rn 5661  df-res 5662  df-ima 5663  df-pred 6306  df-ord 6367  df-on 6368  df-lim 6369  df-suc 6370  df-iota 6496  df-fun 6543  df-fn 6544  df-f 6545  df-f1 6546  df-fo 6547  df-f1o 6548  df-fv 6549  df-riota 7379  df-ov 7425  df-oprab 7426  df-mpo 7427  df-om 7880  df-1st 8003  df-2nd 8004  df-frecs 8304  df-wrecs 8335  df-recs 8384  df-rdg 8423  df-1o 8481  df-er 8722  df-en 8979  df-dom 8980  df-sdom 8981  df-fin 8982  df-card 10025  df-pnf 11350  df-mnf 11351  df-xr 11352  df-ltxr 11353  df-le 11354  df-sub 11548  df-neg 11549  df-nn 12341  df-2 12410  df-3 12411  df-n0 12612  df-z 12699  df-uz 12971  df-fz 13645  df-fzo 13794  df-hash 14480  df-word 14664  df-concat 14721  df-s1 14748  df-s2 15005  df-s3 15006

This theorem is used by:  elwwlks2s3  30547