| Step | Hyp | Ref
| Expression |
| 1 | | frgp0.m |
. . 3
freeGrp   |
| 2 | | eqid 2622 |
. . 3
freeMnd    freeMnd     |
| 3 | | frgp0.r |
. . 3
~FG    |
| 4 | 1, 2, 3 | frgpval 18171 |
. 2
  freeMnd    s   |
| 5 | | 2on 7568 |
. . . . 5
 |
| 6 | | xpexg 6960 |
. . . . 5
    
  |
| 7 | 5, 6 | mpan2 707 |
. . . 4
     |
| 8 | | eqid 2622 |
. . . . 5
   freeMnd        freeMnd      |
| 9 | 2, 8 | frmdbas 17389 |
. . . 4
      freeMnd     Word     |
| 10 | 7, 9 | syl 17 |
. . 3
    freeMnd     Word     |
| 11 | 10 | eqcomd 2628 |
. 2
 Word      freeMnd       |
| 12 | | eqidd 2623 |
. 2
   freeMnd       freeMnd       |
| 13 | | eqid 2622 |
. . . 4
Word    Word
    |
| 14 | 13, 3 | efger 18131 |
. . 3
Word     |
| 15 | | wrdexg 13315 |
. . . . 5
   Word     |
| 16 | | fvi 6255 |
. . . . 5
Word   Word    Word     |
| 17 | 7, 15, 16 | 3syl 18 |
. . . 4
 Word    Word     |
| 18 | | ereq2 7750 |
. . . 4
 Word
   Word  
Word    Word      |
| 19 | 17, 18 | syl 17 |
. . 3
 Word 
 
Word      |
| 20 | 14, 19 | mpbii 223 |
. 2
 Word     |
| 21 | | fvexd 6203 |
. 2
 freeMnd      |
| 22 | | eqid 2622 |
. . . 4
  freeMnd       freeMnd      |
| 23 | 1, 2, 3, 22 | frgpcpbl 18172 |
. . 3
       freeMnd           freeMnd         |
| 24 | 23 | a1i 11 |
. 2
  

  
 freeMnd           freeMnd          |
| 25 | 2 | frmdmnd 17396 |
. . . . . 6
   freeMnd      |
| 26 | 7, 25 | syl 17 |
. . . . 5
 freeMnd      |
| 27 | 26 | 3ad2ant1 1082 |
. . . 4
 
Word   Word    freeMnd      |
| 28 | | simp2 1062 |
. . . . 5
 
Word   Word    Word     |
| 29 | 11 | 3ad2ant1 1082 |
. . . . 5
 
Word   Word    Word      freeMnd       |
| 30 | 28, 29 | eleqtrd 2703 |
. . . 4
 
Word   Word       freeMnd       |
| 31 | | simp3 1063 |
. . . . 5
 
Word   Word    Word     |
| 32 | 31, 29 | eleqtrd 2703 |
. . . 4
 
Word   Word       freeMnd       |
| 33 | 8, 22 | mndcl 17301 |
. . . 4
  freeMnd   
   freeMnd        freeMnd          freeMnd          freeMnd       |
| 34 | 27, 30, 32, 33 | syl3anc 1326 |
. . 3
 
Word   Word        freeMnd          freeMnd       |
| 35 | 34, 29 | eleqtrrd 2704 |
. 2
 
Word   Word        freeMnd       Word     |
| 36 | 20 | adantr 481 |
. . . 4
  
Word  
Word   Word     Word     |
| 37 | 26 | adantr 481 |
. . . . . 6
  
Word  
Word   Word     freeMnd      |
| 38 | 34 | 3adant3r3 1276 |
. . . . . 6
  
Word  
Word   Word         freeMnd          freeMnd       |
| 39 | | simpr3 1069 |
. . . . . . 7
  
Word  
Word   Word     Word
    |
| 40 | 11 | adantr 481 |
. . . . . . 7
  
Word  
Word   Word     Word 

   freeMnd       |
| 41 | 39, 40 | eleqtrd 2703 |
. . . . . 6
  
Word  
Word   Word        freeMnd       |
| 42 | 8, 22 | mndcl 17301 |
. . . . . 6
  freeMnd   
  
 freeMnd          freeMnd    
   freeMnd     
     freeMnd          freeMnd          freeMnd       |
| 43 | 37, 38, 41, 42 | syl3anc 1326 |
. . . . 5
  
Word  
Word   Word          freeMnd          freeMnd          freeMnd       |
| 44 | 43, 40 | eleqtrrd 2704 |
. . . 4
  
Word  
Word   Word          freeMnd          freeMnd       Word     |
| 45 | 36, 44 | erref 7762 |
. . 3
  
Word  
Word   Word          freeMnd          freeMnd            freeMnd          freeMnd         |
| 46 | 30 | 3adant3r3 1276 |
. . . 4
  
Word  
Word   Word    
   freeMnd       |
| 47 | 32 | 3adant3r3 1276 |
. . . 4
  
Word  
Word   Word        freeMnd       |
| 48 | 8, 22 | mndass 17302 |
. . . 4
  freeMnd   
    freeMnd    
   freeMnd        freeMnd            freeMnd          freeMnd           freeMnd          freeMnd          |
| 49 | 37, 46, 47, 41, 48 | syl13anc 1328 |
. . 3
  
Word  
Word   Word          freeMnd          freeMnd           freeMnd          freeMnd          |
| 50 | 45, 49 | breqtrd 4679 |
. 2
  
Word  
Word   Word          freeMnd          freeMnd           freeMnd          freeMnd          |
| 51 | | wrd0 13330 |
. . 3
Word    |
| 52 | 51 | a1i 11 |
. 2
 Word     |
| 53 | 51, 11 | syl5eleq 2707 |
. . . . . 6
    freeMnd       |
| 54 | 53 | adantr 481 |
. . . . 5
 
Word       freeMnd       |
| 55 | 11 | eleq2d 2687 |
. . . . . 6
  Word
 
   freeMnd        |
| 56 | 55 | biimpa 501 |
. . . . 5
 
Word   
   freeMnd       |
| 57 | 2, 8, 22 | frmdadd 17392 |
. . . . 5
 
   freeMnd        freeMnd          freeMnd        ++    |
| 58 | 54, 56, 57 | syl2anc 693 |
. . . 4
 
Word        freeMnd        ++    |
| 59 | | ccatlid 13369 |
. . . . 5
 Word  
 ++    |
| 60 | 59 | adantl 482 |
. . . 4
 
Word     ++    |
| 61 | 58, 60 | eqtrd 2656 |
. . 3
 
Word        freeMnd         |
| 62 | 20 | adantr 481 |
. . . 4
 
Word    Word     |
| 63 | | simpr 477 |
. . . 4
 
Word   
Word     |
| 64 | 62, 63 | erref 7762 |
. . 3
 
Word      |
| 65 | 61, 64 | eqbrtrd 4675 |
. 2
 
Word        freeMnd         |
| 66 | | revcl 13510 |
. . . 4
 Word  
reverse  Word
    |
| 67 | 66 | adantl 482 |
. . 3
 
Word    reverse  Word     |
| 68 | | eqid 2622 |
. . . . 5
                 |
| 69 | 68 | efgmf 18126 |
. . . 4
                 |
| 70 | 69 | a1i 11 |
. . 3
 
Word     
                |
| 71 | | wrdco 13577 |
. . 3
  reverse  Word                   
         reverse   Word     |
| 72 | 67, 70, 71 | syl2anc 693 |
. 2
 
Word            
reverse   Word     |
| 73 | 11 | adantr 481 |
. . . . 5
 
Word    Word 

   freeMnd       |
| 74 | 72, 73 | eleqtrd 2703 |
. . . 4
 
Word            
reverse      freeMnd       |
| 75 | 2, 8, 22 | frmdadd 17392 |
. . . 4
          
reverse      freeMnd    
   freeMnd     
   
      reverse      freeMnd                
reverse   ++    |
| 76 | 74, 56, 75 | syl2anc 693 |
. . 3
 
Word              reverse      freeMnd          
      reverse   ++    |
| 77 | 17 | eleq2d 2687 |
. . . . 5
  Word   
Word      |
| 78 | 77 | biimpar 502 |
. . . 4
 
Word   
Word      |
| 79 | | eqid 2622 |
. . . . 5
 Word 
               splice                          Word
                splice                          |
| 80 | 13, 3, 68, 79 | efginvrel1 18141 |
. . . 4
 Word 
           
reverse   ++ 
  |
| 81 | 78, 80 | syl 17 |
. . 3
 
Word              reverse   ++    |
| 82 | 76, 81 | eqbrtrd 4675 |
. 2
 
Word              reverse      freeMnd         |
| 83 | 4, 11, 12, 20, 21, 24, 35, 50, 52, 65, 72, 82 | qusgrp2 17533 |
1
 
 
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