Theorem reuccatpfxs1 11519

Description: There is a unique word having the length of a given word increased by 1 with the given word as prefix if there is a unique symbol which extends the given word. (Contributed by Alexander van der Vekens, 6-Oct-2018.) (Revised by AV, 21-Jan-2022.) (Revised by AV, 13-Oct-2022.)

Hypothesis

Ref	Expression
reuccatpfxs1.1	|- F/_ v X

Assertion

Ref	Expression
reuccatpfxs1	|- ( ( W e. Word V /\ A. x e. X ( x e. Word V /\ (♯ ` x ) = ( (♯ ` W ) + 1 ) ) ) -> ( E! v e. V ( W ++ <" v "> ) e. X -> E! x e. X W = ( x prefix (♯ ` W ) ) ) )

Distinct variable groups:   v, V, x   v, W, x   x, X

Allowed substitution hint:   X( v)

Proof of Theorem reuccatpfxs1

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

Step	Hyp	Ref	Expression
1		eleq1w 2299	. . . 4 |- ( x = y -> ( x e. Word V <-> y e. Word V ) )
2		fveqeq2 5704	. . . 4 |- ( x = y -> ( (♯ ` x ) = ( (♯ ` W ) + 1 ) <-> (♯ ` y ) = ( (♯ ` W ) + 1 ) ) )
3	1, 2	anbi12d 477	. . 3 |- ( x = y -> ( ( x e. Word V /\ (♯ ` x ) = ( (♯ ` W ) + 1 ) ) <-> ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) )
4	3	cbvralvw 2790	. 2 |- ( A. x e. X ( x e. Word V /\ (♯ ` x ) = ( (♯ ` W ) + 1 ) ) <-> A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) )
5		reuccatpfxs1.1	. . . . 5 |- F/_ v X
6	5	nfel2 2405	. . . 4 |- F/ v ( W ++ <" u "> ) e. X
7	5	nfel2 2405	. . . 4 |- F/ v ( W ++ <" x "> ) e. X
8		s1eq 11387	. . . . . 6 |- ( v = x -> <" v "> = <" x "> )
9	8	oveq2d 6101	. . . . 5 |- ( v = x -> ( W ++ <" v "> ) = ( W ++ <" x "> ) )
10	9	eleq1d 2307	. . . 4 |- ( v = x -> ( ( W ++ <" v "> ) e. X <-> ( W ++ <" x "> ) e. X ) )
11		s1eq 11387	. . . . . 6 |- ( x = u -> <" x "> = <" u "> )
12	11	oveq2d 6101	. . . . 5 |- ( x = u -> ( W ++ <" x "> ) = ( W ++ <" u "> ) )
13	12	eleq1d 2307	. . . 4 |- ( x = u -> ( ( W ++ <" x "> ) e. X <-> ( W ++ <" u "> ) e. X ) )
14	6, 7, 10, 13	reu8nf 3133	. . 3 |- ( E! v e. V ( W ++ <" v "> ) e. X <-> E. v e. V ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) )
15		nfv 1581	. . . . 5 |- F/ v W e. Word V
16		nfv 1581	. . . . . 6 |- F/ v ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) )
17	5, 16	nfralw 2587	. . . . 5 |- F/ v A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) )
18	15, 17	nfan 1618	. . . 4 |- F/ v ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) )
19		nfv 1581	. . . . 5 |- F/ v W = ( x prefix (♯ ` W ) )
20	5, 19	nfreuw 2726	. . . 4 |- F/ v E! x e. X W = ( x prefix (♯ ` W ) )
21		simprl 535	. . . . . 6 |- ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) -> ( W ++ <" v "> ) e. X )
22		simpl 109	. . . . . . . . . . 11 |- ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) -> W e. Word V )
23	22	ad2antrr 492	. . . . . . . . . 10 |- ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) -> W e. Word V )
24	23	anim1i 340	. . . . . . . . 9 |- ( ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) /\ x e. X ) -> ( W e. Word V /\ x e. X ) )
25		simplrr 542	. . . . . . . . 9 |- ( ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) /\ x e. X ) -> A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) )
26		simp-4r 548	. . . . . . . . 9 |- ( ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) /\ x e. X ) -> A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) )
27		reuccatpfxs1lem 11518	. . . . . . . . 9 |- ( ( ( W e. Word V /\ x e. X ) /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) -> ( W = ( x prefix (♯ ` W ) ) -> x = ( W ++ <" v "> ) ) )
28	24, 25, 26, 27	syl3anc 1278	. . . . . . . 8 |- ( ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) /\ x e. X ) -> ( W = ( x prefix (♯ ` W ) ) -> x = ( W ++ <" v "> ) ) )
29		oveq1 6092	. . . . . . . . . . 11 |- ( x = ( W ++ <" v "> ) -> ( x prefix (♯ ` W ) ) = ( ( W ++ <" v "> ) prefix (♯ ` W ) ) )
30		s1cl 11389	. . . . . . . . . . . . . 14 |- ( v e. V -> <" v "> e. Word V )
31	22, 30	anim12i 338	. . . . . . . . . . . . 13 |- ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) -> ( W e. Word V /\ <" v "> e. Word V ) )
32	31	ad2antrr 492	. . . . . . . . . . . 12 |- ( ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) /\ x e. X ) -> ( W e. Word V /\ <" v "> e. Word V ) )
33		pfxccat1 11474	. . . . . . . . . . . 12 |- ( ( W e. Word V /\ <" v "> e. Word V ) -> ( ( W ++ <" v "> ) prefix (♯ ` W ) ) = W )
34	32, 33	syl 14	. . . . . . . . . . 11 |- ( ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) /\ x e. X ) -> ( ( W ++ <" v "> ) prefix (♯ ` W ) ) = W )
35	29, 34	sylan9eqr 2293	. . . . . . . . . 10 |- ( ( ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) /\ x e. X ) /\ x = ( W ++ <" v "> ) ) -> ( x prefix (♯ ` W ) ) = W )
36	35	eqcomd 2244	. . . . . . . . 9 |- ( ( ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) /\ x e. X ) /\ x = ( W ++ <" v "> ) ) -> W = ( x prefix (♯ ` W ) ) )
37	36	ex 115	. . . . . . . 8 |- ( ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) /\ x e. X ) -> ( x = ( W ++ <" v "> ) -> W = ( x prefix (♯ ` W ) ) ) )
38	28, 37	impbid 129	. . . . . . 7 |- ( ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) /\ x e. X ) -> ( W = ( x prefix (♯ ` W ) ) <-> x = ( W ++ <" v "> ) ) )
39	38	ralrimiva 2623	. . . . . 6 |- ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) -> A. x e. X ( W = ( x prefix (♯ ` W ) ) <-> x = ( W ++ <" v "> ) ) )
40		reu6i 3017	. . . . . 6 |- ( ( ( W ++ <" v "> ) e. X /\ A. x e. X ( W = ( x prefix (♯ ` W ) ) <-> x = ( W ++ <" v "> ) ) ) -> E! x e. X W = ( x prefix (♯ ` W ) ) )
41	21, 39, 40	syl2anc 415	. . . . 5 |- ( ( ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) /\ v e. V ) /\ ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) ) -> E! x e. X W = ( x prefix (♯ ` W ) ) )
42	41	exp31 364	. . . 4 |- ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) -> ( v e. V -> ( ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) -> E! x e. X W = ( x prefix (♯ ` W ) ) ) ) )
43	18, 20, 42	rexlimd 2665	. . 3 |- ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) -> ( E. v e. V ( ( W ++ <" v "> ) e. X /\ A. u e. V ( ( W ++ <" u "> ) e. X -> v = u ) ) -> E! x e. X W = ( x prefix (♯ ` W ) ) ) )
44	14, 43	biimtrid 152	. 2 |- ( ( W e. Word V /\ A. y e. X ( y e. Word V /\ (♯ ` y ) = ( (♯ ` W ) + 1 ) ) ) -> ( E! v e. V ( W ++ <" v "> ) e. X -> E! x e. X W = ( x prefix (♯ ` W ) ) ) )
45	4, 44	sylan2b 287	1 |- ( ( W e. Word V /\ A. x e. X ( x e. Word V /\ (♯ ` x ) = ( (♯ ` W ) + 1 ) ) ) -> ( E! v e. V ( W ++ <" v "> ) e. X -> E! x e. X W = ( x prefix (♯ ` W ) ) ) )

This proof depends on syntax axioms:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1402   e. wcel 2209   F/_wnfc 2379   A.wral 2528   E.wrex 2529   E!wreu 2530   ` cfv 5377  (class class class)co 6085   1c1 8180   + caddc 8182  ♯chash 11214  Word cword 11304   ++ cconcat 11358   <"cs1 11383   prefix cpfx 11444

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-coll 4246  ax-sep 4249  ax-nul 4259  ax-pow 4311  ax-pr 4346  ax-un 4578  ax-setind 4684  ax-iinf 4735  ax-cnex 8270  ax-resscn 8271  ax-1cn 8272  ax-1re 8273  ax-icn 8274  ax-addcl 8275  ax-addrcl 8276  ax-mulcl 8277  ax-mulrcl 8278  ax-addcom 8279  ax-mulcom 8280  ax-addass 8281  ax-mulass 8282  ax-distr 8283  ax-i2m1 8284  ax-0lt1 8285  ax-1rid 8286  ax-0id 8287  ax-rnegex 8288  ax-precex 8289  ax-cnre 8290  ax-pre-ltirr 8291  ax-pre-ltwlin 8292  ax-pre-lttrn 8293  ax-pre-apti 8294  ax-pre-ltadd 8295  ax-pre-mulgt0 8296

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-nel 2516  df-ral 2533  df-rex 2534  df-reu 2535  df-rmo 2536  df-rab 2537  df-v 2823  df-sbc 3052  df-csb 3148  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-if 3639  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-int 3971  df-iun 4014  df-br 4131  df-opab 4193  df-mpt 4194  df-tr 4230  df-id 4438  df-iord 4511  df-on 4513  df-ilim 4514  df-suc 4516  df-iom 4738  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-rn 4785  df-res 4786  df-ima 4787  df-iota 5337  df-fun 5379  df-fn 5380  df-f 5381  df-f1 5382  df-fo 5383  df-f1o 5384  df-fv 5385  df-riota 6038  df-ov 6088  df-oprab 6089  df-mpo 6090  df-1st 6374  df-2nd 6375  df-recs 6576  df-frec 6662  df-1o 6687  df-er 6807  df-en 7023  df-dom 7024  df-fin 7025  df-pnf 8362  df-mnf 8363  df-xr 8364  df-ltxr 8365  df-le 8366  df-sub 8499  df-neg 8500  df-reap 8903  df-ap 8910  df-inn 9305  df-n0 9564  df-z 9645  df-uz 9922  df-fz 10412  df-fzo 10550  df-ihash 11215  df-word 11305  df-lsw 11350  df-concat 11359  df-s1 11384  df-substr 11418  df-pfx 11445

This theorem is used by:  reuccatpfxs1v  11520