Proof of Theorem splval2
| Step | Hyp | Ref
| Expression |
| 1 | | splval2.s |
. . . 4
   ++  ++    |
| 2 | | splval2.a |
. . . . . 6
 Word   |
| 3 | | splval2.b |
. . . . . 6
 Word   |
| 4 | | ccatcl 13359 |
. . . . . 6
  Word
Word   ++  Word   |
| 5 | 2, 3, 4 | syl2anc 693 |
. . . . 5
  ++  Word   |
| 6 | | splval2.c |
. . . . 5
 Word   |
| 7 | | ccatcl 13359 |
. . . . 5
   ++  Word Word    ++  ++  Word   |
| 8 | 5, 6, 7 | syl2anc 693 |
. . . 4
   ++  ++  Word   |
| 9 | 1, 8 | eqeltrd 2701 |
. . 3
 Word   |
| 10 | | splval2.f |
. . . 4
       |
| 11 | | lencl 13324 |
. . . . 5
 Word       |
| 12 | 2, 11 | syl 17 |
. . . 4
       |
| 13 | 10, 12 | eqeltrd 2701 |
. . 3
   |
| 14 | | splval2.t |
. . . 4
         |
| 15 | | lencl 13324 |
. . . . . 6
 Word       |
| 16 | 3, 15 | syl 17 |
. . . . 5
       |
| 17 | 13, 16 | nn0addcld 11355 |
. . . 4
         |
| 18 | 14, 17 | eqeltrd 2701 |
. . 3
   |
| 19 | | splval2.r |
. . 3
 Word   |
| 20 | | splval 13502 |
. . 3
  Word 
Word  
 splice  
      substr     ++  ++  substr            |
| 21 | 9, 13, 18, 19, 20 | syl13anc 1328 |
. 2
  splice   
     substr     ++  ++  substr            |
| 22 | | nn0uz 11722 |
. . . . . . . . . 10
     |
| 23 | 13, 22 | syl6eleq 2711 |
. . . . . . . . 9
       |
| 24 | | eluzfz1 12348 |
. . . . . . . . 9
    
      |
| 25 | 23, 24 | syl 17 |
. . . . . . . 8
       |
| 26 | 13 | nn0zd 11480 |
. . . . . . . . . . . 12
   |
| 27 | | uzid 11702 |
. . . . . . . . . . . 12
       |
| 28 | 26, 27 | syl 17 |
. . . . . . . . . . 11
       |
| 29 | | uzaddcl 11744 |
. . . . . . . . . . 11
           
           |
| 30 | 28, 16, 29 | syl2anc 693 |
. . . . . . . . . 10
             |
| 31 | 14, 30 | eqeltrd 2701 |
. . . . . . . . 9
       |
| 32 | | elfzuzb 12336 |
. . . . . . . . 9
    
    
       |
| 33 | 23, 31, 32 | sylanbrc 698 |
. . . . . . . 8
       |
| 34 | 18, 22 | syl6eleq 2711 |
. . . . . . . . 9
       |
| 35 | | ccatlen 13360 |
. . . . . . . . . . . 12
   ++  Word Word       ++  ++        ++          |
| 36 | 5, 6, 35 | syl2anc 693 |
. . . . . . . . . . 11
      ++  ++        ++          |
| 37 | 1 | fveq2d 6195 |
. . . . . . . . . . 11
          ++  ++     |
| 38 | 10 | oveq1d 6665 |
. . . . . . . . . . . . 13
                   |
| 39 | | ccatlen 13360 |
. . . . . . . . . . . . . 14
  Word
Word      ++               |
| 40 | 2, 3, 39 | syl2anc 693 |
. . . . . . . . . . . . 13
     ++               |
| 41 | 38, 14, 40 | 3eqtr4d 2666 |
. . . . . . . . . . . 12
     ++     |
| 42 | 41 | oveq1d 6665 |
. . . . . . . . . . 11
            ++          |
| 43 | 36, 37, 42 | 3eqtr4d 2666 |
. . . . . . . . . 10
             |
| 44 | 18 | nn0zd 11480 |
. . . . . . . . . . . 12
   |
| 45 | | uzid 11702 |
. . . . . . . . . . . 12
       |
| 46 | 44, 45 | syl 17 |
. . . . . . . . . . 11
       |
| 47 | | lencl 13324 |
. . . . . . . . . . . 12
 Word       |
| 48 | 6, 47 | syl 17 |
. . . . . . . . . . 11
       |
| 49 | | uzaddcl 11744 |
. . . . . . . . . . 11
           
           |
| 50 | 46, 48, 49 | syl2anc 693 |
. . . . . . . . . 10
             |
| 51 | 43, 50 | eqeltrd 2701 |
. . . . . . . . 9
           |
| 52 | | elfzuzb 12336 |
. . . . . . . . 9
        
                |
| 53 | 34, 51, 52 | sylanbrc 698 |
. . . . . . . 8
           |
| 54 | | ccatswrd 13456 |
. . . . . . . 8
  Word                   
  substr     ++  substr       substr       |
| 55 | 9, 25, 33, 53, 54 | syl13anc 1328 |
. . . . . . 7
   substr     ++  substr       substr       |
| 56 | | eluzfz1 12348 |
. . . . . . . . . . . 12
    
      |
| 57 | 34, 56 | syl 17 |
. . . . . . . . . . 11
       |
| 58 | | lencl 13324 |
. . . . . . . . . . . . . 14
 Word       |
| 59 | 9, 58 | syl 17 |
. . . . . . . . . . . . 13
       |
| 60 | 59, 22 | syl6eleq 2711 |
. . . . . . . . . . . 12
           |
| 61 | | eluzfz2 12349 |
. . . . . . . . . . . 12
                       |
| 62 | 60, 61 | syl 17 |
. . . . . . . . . . 11
               |
| 63 | | ccatswrd 13456 |
. . . . . . . . . . 11
  Word                              substr     ++  substr           substr           |
| 64 | 9, 57, 53, 62, 63 | syl13anc 1328 |
. . . . . . . . . 10
   substr     ++  substr           substr           |
| 65 | | swrdid 13428 |
. . . . . . . . . . 11
 Word  substr           |
| 66 | 9, 65 | syl 17 |
. . . . . . . . . 10
  substr           |
| 67 | 64, 66, 1 | 3eqtrd 2660 |
. . . . . . . . 9
   substr     ++  substr            ++  ++    |
| 68 | | swrdcl 13419 |
. . . . . . . . . . 11
 Word  substr     Word   |
| 69 | 9, 68 | syl 17 |
. . . . . . . . . 10
  substr     Word   |
| 70 | | swrdcl 13419 |
. . . . . . . . . . 11
 Word  substr         Word   |
| 71 | 9, 70 | syl 17 |
. . . . . . . . . 10
  substr        
Word   |
| 72 | | swrd0len 13422 |
. . . . . . . . . . . 12
  Word
             substr        |
| 73 | 9, 53, 72 | syl2anc 693 |
. . . . . . . . . . 11
     substr        |
| 74 | 73, 41 | eqtrd 2656 |
. . . . . . . . . 10
     substr          ++     |
| 75 | | ccatopth 13470 |
. . . . . . . . . 10
    substr     Word  substr        
Word    ++  Word
Word      substr          ++       substr     ++  substr            ++  ++ 
  substr      ++   substr             |
| 76 | 69, 71, 5, 6, 74, 75 | syl221anc 1337 |
. . . . . . . . 9
    substr     ++  substr            ++  ++ 
  substr      ++   substr             |
| 77 | 67, 76 | mpbid 222 |
. . . . . . . 8
   substr      ++  
substr        
   |
| 78 | 77 | simpld 475 |
. . . . . . 7
  substr      ++    |
| 79 | 55, 78 | eqtrd 2656 |
. . . . . 6
   substr     ++  substr       ++    |
| 80 | | swrdcl 13419 |
. . . . . . . 8
 Word  substr     Word   |
| 81 | 9, 80 | syl 17 |
. . . . . . 7
  substr     Word   |
| 82 | | swrdcl 13419 |
. . . . . . . 8
 Word  substr     Word   |
| 83 | 9, 82 | syl 17 |
. . . . . . 7
  substr     Word   |
| 84 | | uztrn 11704 |
. . . . . . . . . . 11
              
          |
| 85 | 51, 31, 84 | syl2anc 693 |
. . . . . . . . . 10
           |
| 86 | | elfzuzb 12336 |
. . . . . . . . . 10
        
                |
| 87 | 23, 85, 86 | sylanbrc 698 |
. . . . . . . . 9
           |
| 88 | | swrd0len 13422 |
. . . . . . . . 9
  Word
             substr        |
| 89 | 9, 87, 88 | syl2anc 693 |
. . . . . . . 8
     substr        |
| 90 | 89, 10 | eqtrd 2656 |
. . . . . . 7
     substr            |
| 91 | | ccatopth 13470 |
. . . . . . 7
    substr     Word  substr     Word 
 Word Word      substr              substr     ++  substr       ++ 
  substr     
substr         |
| 92 | 81, 83, 2, 3, 90, 91 | syl221anc 1337 |
. . . . . 6
    substr     ++  substr       ++    substr      substr         |
| 93 | 79, 92 | mpbid 222 |
. . . . 5
   substr      substr        |
| 94 | 93 | simpld 475 |
. . . 4
  substr       |
| 95 | 94 | oveq1d 6665 |
. . 3
   substr     ++   ++    |
| 96 | 77 | simprd 479 |
. . 3
  substr        
  |
| 97 | 95, 96 | oveq12d 6668 |
. 2
    substr     ++  ++  substr            ++  ++    |
| 98 | 21, 97 | eqtrd 2656 |
1
  splice   
    ++  ++    |