Theorem wrdl3s3 14605

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 10900	. . . . . . . 8 ⊢ 0 ∈ V
2	1	tpid1 4701	. . . . . . 7 ⊢ 0 ∈ {0, 1, 2}
3		fzo0to3tp 13401	. . . . . . 7 ⊢ (0..^3) = {0, 1, 2}
4	2, 3	eleqtrri 2838	. . . . . 6 ⊢ 0 ∈ (0..^3)
5		oveq2 7263	. . . . . 6 ⊢ ((♯‘𝑊) = 3 → (0..^(♯‘𝑊)) = (0..^3))
6	4, 5	eleqtrrid 2846	. . . . 5 ⊢ ((♯‘𝑊) = 3 → 0 ∈ (0..^(♯‘𝑊)))
7		wrdsymbcl 14158	. . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 0 ∈ (0..^(♯‘𝑊))) → (𝑊‘0) ∈ 𝑉)
8	6, 7	sylan2 592	. . . 4 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → (𝑊‘0) ∈ 𝑉)
9		1ex 10902	. . . . . . . 8 ⊢ 1 ∈ V
10	9	tpid2 4703	. . . . . . 7 ⊢ 1 ∈ {0, 1, 2}
11	10, 3	eleqtrri 2838	. . . . . 6 ⊢ 1 ∈ (0..^3)
12	11, 5	eleqtrrid 2846	. . . . 5 ⊢ ((♯‘𝑊) = 3 → 1 ∈ (0..^(♯‘𝑊)))
13		wrdsymbcl 14158	. . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 1 ∈ (0..^(♯‘𝑊))) → (𝑊‘1) ∈ 𝑉)
14	12, 13	sylan2 592	. . . 4 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → (𝑊‘1) ∈ 𝑉)
15		2ex 11980	. . . . . . . 8 ⊢ 2 ∈ V
16	15	tpid3 4706	. . . . . . 7 ⊢ 2 ∈ {0, 1, 2}
17	16, 3	eleqtrri 2838	. . . . . 6 ⊢ 2 ∈ (0..^3)
18	17, 5	eleqtrrid 2846	. . . . 5 ⊢ ((♯‘𝑊) = 3 → 2 ∈ (0..^(♯‘𝑊)))
19		wrdsymbcl 14158	. . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 2 ∈ (0..^(♯‘𝑊))) → (𝑊‘2) ∈ 𝑉)
20	18, 19	sylan2 592	. . . 4 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → (𝑊‘2) ∈ 𝑉)
21		simpr 484	. . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → (♯‘𝑊) = 3)
22		eqid 2738	. . . . . 6 ⊢ (𝑊‘0) = (𝑊‘0)
23		eqid 2738	. . . . . 6 ⊢ (𝑊‘1) = (𝑊‘1)
24		eqid 2738	. . . . . 6 ⊢ (𝑊‘2) = (𝑊‘2)
25	22, 23, 24	3pm3.2i 1337	. . . . 5 ⊢ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = (𝑊‘2))
26	21, 25	jctir 520	. . . 4 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = (𝑊‘1) ∧ (𝑊‘2) = (𝑊‘2))))
27		eqeq2 2750	. . . . . . 7 ⊢ (𝑎 = (𝑊‘0) → ((𝑊‘0) = 𝑎 ↔ (𝑊‘0) = (𝑊‘0)))
28	27	3anbi1d 1438	. . . . . 6 ⊢ (𝑎 = (𝑊‘0) → (((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐) ↔ ((𝑊‘0) = (𝑊‘0) ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)))
29	28	anbi2d 628	. . . . 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))))
30		eqeq2 2750	. . . . . . 7 ⊢ (𝑏 = (𝑊‘1) → ((𝑊‘1) = 𝑏 ↔ (𝑊‘1) = (𝑊‘1)))
31	30	3anbi2d 1439	. . . . . 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)))
32	31	anbi2d 628	. . . . 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))))
33		eqeq2 2750	. . . . . . 7 ⊢ (𝑐 = (𝑊‘2) → ((𝑊‘2) = 𝑐 ↔ (𝑊‘2) = (𝑊‘2)))
34	33	3anbi3d 1440	. . . . . 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))))
35	34	anbi2d 628	. . . . 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)))))
36	29, 32, 35	rspc3ev 3566	. . . 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)))
37	8, 14, 20, 26, 36	syl31anc 1371	. . 3 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → ∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)))
38		df-3an 1087	. . . . . . . . 9 ⊢ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉 ∧ 𝑐 ∈ 𝑉) ↔ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉))
39		eqwrds3 14604	. . . . . . . . . 10 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉 ∧ 𝑐 ∈ 𝑉)) → (𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐))))
40	39	ex 412	. . . . . . . . 9 ⊢ (𝑊 ∈ Word 𝑉 → ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉 ∧ 𝑐 ∈ 𝑉) → (𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)))))
41	38, 40	syl5bir 242	. . . . . . . 8 ⊢ (𝑊 ∈ Word 𝑉 → (((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) → (𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐)))))
42	41	expd 415	. . . . . . 7 ⊢ (𝑊 ∈ Word 𝑉 → ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → (𝑐 ∈ 𝑉 → (𝑊 = ⟨“𝑎𝑏𝑐”⟩ ↔ ((♯‘𝑊) = 3 ∧ ((𝑊‘0) = 𝑎 ∧ (𝑊‘1) = 𝑏 ∧ (𝑊‘2) = 𝑐))))))
43	42	adantr 480	. . . . . 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))))))
44	43	imp31 417	. . . . 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))))
45	44	rexbidva 3224	. . . 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))))
46	45	2rexbidva 3227	. . 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))))
47	37, 46	mpbird 256	. 2 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) → ∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩)
48		s3cl 14520	. . . . . . 7 ⊢ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉 ∧ 𝑐 ∈ 𝑉) → ⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉)
49	48	ad4ant123 1170	. . . . . 6 ⊢ ((((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) ∧ 𝑊 = ⟨“𝑎𝑏𝑐”⟩) → ⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉)
50		s3len 14535	. . . . . 6 ⊢ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3
51	49, 50	jctir 520	. . . . 5 ⊢ ((((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) ∧ 𝑊 = ⟨“𝑎𝑏𝑐”⟩) → (⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉 ∧ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3))
52		eleq1 2826	. . . . . . 7 ⊢ (𝑊 = ⟨“𝑎𝑏𝑐”⟩ → (𝑊 ∈ Word 𝑉 ↔ ⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉))
53		fveqeq2 6765	. . . . . . 7 ⊢ (𝑊 = ⟨“𝑎𝑏𝑐”⟩ → ((♯‘𝑊) = 3 ↔ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3))
54	52, 53	anbi12d 630	. . . . . 6 ⊢ (𝑊 = ⟨“𝑎𝑏𝑐”⟩ → ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) ↔ (⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉 ∧ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3)))
55	54	adantl 481	. . . . 5 ⊢ ((((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) ∧ 𝑊 = ⟨“𝑎𝑏𝑐”⟩) → ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) ↔ (⟨“𝑎𝑏𝑐”⟩ ∈ Word 𝑉 ∧ (♯‘⟨“𝑎𝑏𝑐”⟩) = 3)))
56	51, 55	mpbird 256	. . . 4 ⊢ ((((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ∧ 𝑐 ∈ 𝑉) ∧ 𝑊 = ⟨“𝑎𝑏𝑐”⟩) → (𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3))
57	56	rexlimdva2 3215	. . 3 ⊢ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → (∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩ → (𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3)))
58	57	rexlimivv 3220	. 2 ⊢ (∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩ → (𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3))
59	47, 58	impbii 208	1 ⊢ ((𝑊 ∈ Word 𝑉 ∧ (♯‘𝑊) = 3) ↔ ∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 ∃𝑐 ∈ 𝑉 𝑊 = ⟨“𝑎𝑏𝑐”⟩)

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 395   ∧ w3a 1085   = wceq 1539   ∈ wcel 2108  ∃wrex 3064  {ctp 4562  ‘cfv 6418  (class class class)co 7255  0cc0 10802  1c1 10803  2c2 11958  3c3 11959  ..^cfzo 13311  ♯chash 13972  Word cword 14145  ⟨“cs3 14483

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1799  ax-4 1813  ax-5 1914  ax-6 1972  ax-7 2012  ax-8 2110  ax-9 2118  ax-10 2139  ax-11 2156  ax-12 2173  ax-ext 2709  ax-rep 5205  ax-sep 5218  ax-nul 5225  ax-pow 5283  ax-pr 5347  ax-un 7566  ax-cnex 10858  ax-resscn 10859  ax-1cn 10860  ax-icn 10861  ax-addcl 10862  ax-addrcl 10863  ax-mulcl 10864  ax-mulrcl 10865  ax-mulcom 10866  ax-addass 10867  ax-mulass 10868  ax-distr 10869  ax-i2m1 10870  ax-1ne0 10871  ax-1rid 10872  ax-rnegex 10873  ax-rrecex 10874  ax-cnre 10875  ax-pre-lttri 10876  ax-pre-lttrn 10877  ax-pre-ltadd 10878  ax-pre-mulgt0 10879

This theorem depends on definitions:  df-bi 206  df-an 396  df-or 844  df-3or 1086  df-3an 1087  df-tru 1542  df-fal 1552  df-ex 1784  df-nf 1788  df-sb 2069  df-mo 2540  df-eu 2569  df-clab 2716  df-cleq 2730  df-clel 2817  df-nfc 2888  df-ne 2943  df-nel 3049  df-ral 3068  df-rex 3069  df-reu 3070  df-rab 3072  df-v 3424  df-sbc 3712  df-csb 3829  df-dif 3886  df-un 3888  df-in 3890  df-ss 3900  df-pss 3902  df-nul 4254  df-if 4457  df-pw 4532  df-sn 4559  df-pr 4561  df-tp 4563  df-op 4565  df-uni 4837  df-int 4877  df-iun 4923  df-br 5071  df-opab 5133  df-mpt 5154  df-tr 5188  df-id 5480  df-eprel 5486  df-po 5494  df-so 5495  df-fr 5535  df-we 5537  df-xp 5586  df-rel 5587  df-cnv 5588  df-co 5589  df-dm 5590  df-rn 5591  df-res 5592  df-ima 5593  df-pred 6191  df-ord 6254  df-on 6255  df-lim 6256  df-suc 6257  df-iota 6376  df-fun 6420  df-fn 6421  df-f 6422  df-f1 6423  df-fo 6424  df-f1o 6425  df-fv 6426  df-riota 7212  df-ov 7258  df-oprab 7259  df-mpo 7260  df-om 7688  df-1st 7804  df-2nd 7805  df-frecs 8068  df-wrecs 8099  df-recs 8173  df-rdg 8212  df-1o 8267  df-er 8456  df-en 8692  df-dom 8693  df-sdom 8694  df-fin 8695  df-card 9628  df-pnf 10942  df-mnf 10943  df-xr 10944  df-ltxr 10945  df-le 10946  df-sub 11137  df-neg 11138  df-nn 11904  df-2 11966  df-3 11967  df-n0 12164  df-z 12250  df-uz 12512  df-fz 13169  df-fzo 13312  df-hash 13973  df-word 14146  df-concat 14202  df-s1 14229  df-s2 14489  df-s3 14490

This theorem is referenced by:  elwwlks2s3  28217