Theorem wrdl3s3 15108

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 11293	. . . . . . . 8 ⊢ 0 ∈ V
2	1	tpid1 4729	. . . . . . 7 ⊢ 0 ∈ {0, 1, 2}
3		fzo0to3tp 13880	. . . . . . 7 ⊢ (0..^3) = {0, 1, 2}
4	2, 3	eleqtrri 2860	. . . . . 6 ⊢ 0 ∈ (0..^3)
5		oveq2 7426	. . . . . 6 ⊢ ((♯‘𝑊) = 3 → (0..^(♯‘𝑊)) = (0..^3))
6	4, 5	eleqtrrid 2868	. . . . 5 ⊢ ((♯‘𝑊) = 3 → 0 ∈ (0..^(♯‘𝑊)))
7		wrdsymbcl 14665	. . . . 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 12406	. . . . . . 7 ⊢ 1 ∈ {0, 1, 2}
10	9, 3	eleqtrri 2860	. . . . . 6 ⊢ 1 ∈ (0..^3)
11	10, 5	eleqtrrid 2868	. . . . 5 ⊢ ((♯‘𝑊) = 3 → 1 ∈ (0..^(♯‘𝑊)))
12		wrdsymbcl 14665	. . . . 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 12413	. . . . . . . 8 ⊢ 2 ∈ V
15	14	tpid3 4734	. . . . . . 7 ⊢ 2 ∈ {0, 1, 2}
16	15, 3	eleqtrri 2860	. . . . . 6 ⊢ 2 ∈ (0..^3)
17	16, 5	eleqtrrid 2868	. . . . 5 ⊢ ((♯‘𝑊) = 3 → 2 ∈ (0..^(♯‘𝑊)))
18		wrdsymbcl 14665	. . . . 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 2761	. . . . . 6 ⊢ (𝑊‘0) = (𝑊‘0)
22		eqid 2761	. . . . . 6 ⊢ (𝑊‘1) = (𝑊‘1)
23		eqid 2761	. . . . . 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 2773	. . . . . . 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 2773	. . . . . . 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 2773	. . . . . . 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 3593	. . . 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 15107	. . . . . . . . . 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 3185	. . . 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 3226	. . 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 15023	. . . . . . 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 15038	. . . . . 6 ⊢ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3
50	48, 49	jctir 530	. . . . 5 ⊢ ((((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) ∧ 𝑊 = ⟨“𝑎𝑏𝑐”⟩) → (⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉 ∧ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3))
51		eleq1 2849	. . . . . . 7 ⊢ (𝑊 = ⟨“𝑎𝑏𝑐”⟩ → (𝑊 ∈ Word 𝑉 ↔ ⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉))
52		fveqeq2 6892	. . . . . . 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 3166	. . 3 ⊢ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → (∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩ → (𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3)))
57	56	rexlimivv 3205	. 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 1570   ∈ wcel 2145  ∃wrex 3087  {ctp 4588  ‘cfv 6537  (class class class)co 7418  0cc0 11193  1c1 11194  2c2 12390  3c3 12391  ..^cfzo 13781  ♯chash 14467  Word cword 14651  ⟨“cs3 14986

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2213  ax-ext 2733  ax-rep 5232  ax-sep 5249  ax-nul 5260  ax-pow 5327  ax-pr 5391  ax-un 7749  ax-cnex 11249  ax-resscn 11250  ax-1cn 11251  ax-icn 11252  ax-addcl 11253  ax-addrcl 11254  ax-mulcl 11255  ax-mulrcl 11256  ax-mulcom 11257  ax-addass 11258  ax-mulass 11259  ax-distr 11260  ax-i2m1 11261  ax-1ne0 11262  ax-1rid 11263  ax-rnegex 11264  ax-rrecex 11265  ax-cnre 11266  ax-pre-lttri 11267  ax-pre-lttrn 11268  ax-pre-ltadd 11269  ax-pre-mulgt0 11270

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2565  df-eu 2595  df-clab 2740  df-cleq 2753  df-clel 2836  df-nfc 2910  df-ne 2957  df-nel 3063  df-ral 3078  df-rex 3088  df-reu 3367  df-rab 3414  df-v 3453  df-sbc 3740  df-csb 3848  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-pss 3919  df-nul 4280  df-if 4483  df-pw 4559  df-sn 4585  df-pr 4587  df-tp 4589  df-op 4591  df-uni 4868  df-int 4908  df-iun 4953  df-br 5104  df-opab 5168  df-mpt 5187  df-tr 5213  df-id 5546  df-eprel 5551  df-po 5559  df-so 5560  df-fr 5604  df-we 5606  df-xp 5657  df-rel 5658  df-cnv 5659  df-co 5660  df-dm 5661  df-rn 5662  df-res 5663  df-ima 5664  df-pred 6303  df-ord 6364  df-on 6365  df-lim 6366  df-suc 6367  df-iota 6493  df-fun 6539  df-fn 6540  df-f 6541  df-f1 6542  df-fo 6543  df-f1o 6544  df-fv 6545  df-riota 7375  df-ov 7421  df-oprab 7422  df-mpo 7423  df-om 7876  df-1st 7999  df-2nd 8000  df-frecs 8292  df-wrecs 8323  df-recs 8372  df-rdg 8411  df-1o 8469  df-er 8710  df-en 8967  df-dom 8968  df-sdom 8969  df-fin 8970  df-card 10013  df-pnf 11338  df-mnf 11339  df-xr 11340  df-ltxr 11341  df-le 11342  df-sub 11536  df-neg 11537  df-nn 12329  df-2 12398  df-3 12399  df-n0 12600  df-z 12687  df-uz 12959  df-fz 13633  df-fzo 13782  df-hash 14468  df-word 14652  df-concat 14709  df-s1 14736  df-s2 14992  df-s3 14993

This theorem is used by:  elwwlks2s3  30533