Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > MPE Home > Th. List > ccats1pfxeqrex | Structured version Visualization version GIF version |
Description: There exists a symbol such that its concatenation after the prefix obtained by deleting the last symbol of a nonempty word results in the word itself. (Contributed by AV, 5-Oct-2018.) (Revised by AV, 9-May-2020.) |
Ref | Expression |
---|---|
ccats1pfxeqrex | ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉 ∧ (♯‘𝑈) = ((♯‘𝑊) + 1)) → (𝑊 = (𝑈 prefix (♯‘𝑊)) → ∃𝑠 ∈ 𝑉 𝑈 = (𝑊 ++ 〈“𝑠”〉))) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | simp2 1139 | . . 3 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉 ∧ (♯‘𝑈) = ((♯‘𝑊) + 1)) → 𝑈 ∈ Word 𝑉) | |
2 | lencl 14071 | . . . . . . 7 ⊢ (𝑊 ∈ Word 𝑉 → (♯‘𝑊) ∈ ℕ0) | |
3 | 2 | 3ad2ant1 1135 | . . . . . 6 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉 ∧ (♯‘𝑈) = ((♯‘𝑊) + 1)) → (♯‘𝑊) ∈ ℕ0) |
4 | nn0p1nn 12112 | . . . . . 6 ⊢ ((♯‘𝑊) ∈ ℕ0 → ((♯‘𝑊) + 1) ∈ ℕ) | |
5 | nngt0 11844 | . . . . . 6 ⊢ (((♯‘𝑊) + 1) ∈ ℕ → 0 < ((♯‘𝑊) + 1)) | |
6 | 3, 4, 5 | 3syl 18 | . . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉 ∧ (♯‘𝑈) = ((♯‘𝑊) + 1)) → 0 < ((♯‘𝑊) + 1)) |
7 | breq2 5047 | . . . . . 6 ⊢ ((♯‘𝑈) = ((♯‘𝑊) + 1) → (0 < (♯‘𝑈) ↔ 0 < ((♯‘𝑊) + 1))) | |
8 | 7 | 3ad2ant3 1137 | . . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉 ∧ (♯‘𝑈) = ((♯‘𝑊) + 1)) → (0 < (♯‘𝑈) ↔ 0 < ((♯‘𝑊) + 1))) |
9 | 6, 8 | mpbird 260 | . . . 4 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉 ∧ (♯‘𝑈) = ((♯‘𝑊) + 1)) → 0 < (♯‘𝑈)) |
10 | hashgt0n0 13915 | . . . 4 ⊢ ((𝑈 ∈ Word 𝑉 ∧ 0 < (♯‘𝑈)) → 𝑈 ≠ ∅) | |
11 | 1, 9, 10 | syl2anc 587 | . . 3 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉 ∧ (♯‘𝑈) = ((♯‘𝑊) + 1)) → 𝑈 ≠ ∅) |
12 | lswcl 14106 | . . 3 ⊢ ((𝑈 ∈ Word 𝑉 ∧ 𝑈 ≠ ∅) → (lastS‘𝑈) ∈ 𝑉) | |
13 | 1, 11, 12 | syl2anc 587 | . 2 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉 ∧ (♯‘𝑈) = ((♯‘𝑊) + 1)) → (lastS‘𝑈) ∈ 𝑉) |
14 | ccats1pfxeq 14262 | . 2 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉 ∧ (♯‘𝑈) = ((♯‘𝑊) + 1)) → (𝑊 = (𝑈 prefix (♯‘𝑊)) → 𝑈 = (𝑊 ++ 〈“(lastS‘𝑈)”〉))) | |
15 | s1eq 14140 | . . . 4 ⊢ (𝑠 = (lastS‘𝑈) → 〈“𝑠”〉 = 〈“(lastS‘𝑈)”〉) | |
16 | 15 | oveq2d 7218 | . . 3 ⊢ (𝑠 = (lastS‘𝑈) → (𝑊 ++ 〈“𝑠”〉) = (𝑊 ++ 〈“(lastS‘𝑈)”〉)) |
17 | 16 | rspceeqv 3545 | . 2 ⊢ (((lastS‘𝑈) ∈ 𝑉 ∧ 𝑈 = (𝑊 ++ 〈“(lastS‘𝑈)”〉)) → ∃𝑠 ∈ 𝑉 𝑈 = (𝑊 ++ 〈“𝑠”〉)) |
18 | 13, 14, 17 | syl6an 684 | 1 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉 ∧ (♯‘𝑈) = ((♯‘𝑊) + 1)) → (𝑊 = (𝑈 prefix (♯‘𝑊)) → ∃𝑠 ∈ 𝑉 𝑈 = (𝑊 ++ 〈“𝑠”〉))) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ↔ wb 209 ∧ w3a 1089 = wceq 1543 ∈ wcel 2110 ≠ wne 2935 ∃wrex 3055 ∅c0 4227 class class class wbr 5043 ‘cfv 6369 (class class class)co 7202 0cc0 10712 1c1 10713 + caddc 10715 < clt 10850 ℕcn 11813 ℕ0cn0 12073 ♯chash 13879 Word cword 14052 lastSclsw 14100 ++ cconcat 14108 〈“cs1 14135 prefix cpfx 14218 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1803 ax-4 1817 ax-5 1918 ax-6 1976 ax-7 2016 ax-8 2112 ax-9 2120 ax-10 2141 ax-11 2158 ax-12 2175 ax-ext 2706 ax-rep 5168 ax-sep 5181 ax-nul 5188 ax-pow 5247 ax-pr 5311 ax-un 7512 ax-cnex 10768 ax-resscn 10769 ax-1cn 10770 ax-icn 10771 ax-addcl 10772 ax-addrcl 10773 ax-mulcl 10774 ax-mulrcl 10775 ax-mulcom 10776 ax-addass 10777 ax-mulass 10778 ax-distr 10779 ax-i2m1 10780 ax-1ne0 10781 ax-1rid 10782 ax-rnegex 10783 ax-rrecex 10784 ax-cnre 10785 ax-pre-lttri 10786 ax-pre-lttrn 10787 ax-pre-ltadd 10788 ax-pre-mulgt0 10789 |
This theorem depends on definitions: df-bi 210 df-an 400 df-or 848 df-3or 1090 df-3an 1091 df-tru 1546 df-fal 1556 df-ex 1788 df-nf 1792 df-sb 2071 df-mo 2537 df-eu 2566 df-clab 2713 df-cleq 2726 df-clel 2812 df-nfc 2882 df-ne 2936 df-nel 3040 df-ral 3059 df-rex 3060 df-reu 3061 df-rab 3063 df-v 3403 df-sbc 3688 df-csb 3803 df-dif 3860 df-un 3862 df-in 3864 df-ss 3874 df-pss 3876 df-nul 4228 df-if 4430 df-pw 4505 df-sn 4532 df-pr 4534 df-tp 4536 df-op 4538 df-uni 4810 df-int 4850 df-iun 4896 df-br 5044 df-opab 5106 df-mpt 5125 df-tr 5151 df-id 5444 df-eprel 5449 df-po 5457 df-so 5458 df-fr 5498 df-we 5500 df-xp 5546 df-rel 5547 df-cnv 5548 df-co 5549 df-dm 5550 df-rn 5551 df-res 5552 df-ima 5553 df-pred 6149 df-ord 6205 df-on 6206 df-lim 6207 df-suc 6208 df-iota 6327 df-fun 6371 df-fn 6372 df-f 6373 df-f1 6374 df-fo 6375 df-f1o 6376 df-fv 6377 df-riota 7159 df-ov 7205 df-oprab 7206 df-mpo 7207 df-om 7634 df-1st 7750 df-2nd 7751 df-wrecs 8036 df-recs 8097 df-rdg 8135 df-1o 8191 df-er 8380 df-en 8616 df-dom 8617 df-sdom 8618 df-fin 8619 df-card 9538 df-pnf 10852 df-mnf 10853 df-xr 10854 df-ltxr 10855 df-le 10856 df-sub 11047 df-neg 11048 df-nn 11814 df-n0 12074 df-xnn0 12146 df-z 12160 df-uz 12422 df-fz 13079 df-fzo 13222 df-hash 13880 df-word 14053 df-lsw 14101 df-concat 14109 df-s1 14136 df-substr 14189 df-pfx 14219 |
This theorem is referenced by: reuccatpfxs1lem 14294 |
Copyright terms: Public domain | W3C validator |