Proof of Theorem grplcan
| Step | Hyp | Ref
| Expression |
| 1 | | opreq2 3969 |
. . . . . . 7
           inv              inv              |
| 2 | 1 | adantl 388 |
. . . . . 6
    Grp  
             inv              inv              |
| 3 | | grplcan.1 |
. . . . . . . . . . . 12
 |
| 4 | | eqid 1475 |
. . . . . . . . . . . 12
Id  Id   |
| 5 | | eqid 1475 |
. . . . . . . . . . . 12
inv  inv   |
| 6 | 3, 4, 5 | grplinv 8070 |
. . . . . . . . . . 11
  Grp
   inv        Id    |
| 7 | 6 | adantlr 393 |
. . . . . . . . . 10
   Grp

   inv        Id    |
| 8 | 7 | opreq1d 3975 |
. . . . . . . . 9
   Grp

    inv            Id       |
| 9 | 3, 5 | grpinvcl 8068 |
. . . . . . . . . . . . 13
  Grp
  inv       |
| 10 | 9 | adantrl 394 |
. . . . . . . . . . . 12
  Grp     inv       |
| 11 | | simprr 415 |
. . . . . . . . . . . 12
  Grp      |
| 12 | | simprl 414 |
. . . . . . . . . . . 12
  Grp      |
| 13 | 10, 11, 12 | 3jca 819 |
. . . . . . . . . . 11
  Grp      inv        |
| 14 | 3 | grpass 8047 |
. . . . . . . . . . 11
  Grp   inv    
     inv             inv              |
| 15 | 13, 14 | syldan 467 |
. . . . . . . . . 10
  Grp       inv             inv              |
| 16 | 15 | anassrs 441 |
. . . . . . . . 9
   Grp

    inv             inv              |
| 17 | 3, 4 | grplid 8061 |
. . . . . . . . . 10
  Grp
  Id       |
| 18 | 17 | adantr 389 |
. . . . . . . . 9
   Grp

  Id       |
| 19 | 8, 16, 18 | 3eqtr3d 1515 |
. . . . . . . 8
   Grp

   inv              |
| 20 | 19 | adantrl 394 |
. . . . . . 7
   Grp


    inv              |
| 21 | 20 | adantr 389 |
. . . . . 6
    Grp  
             inv              |
| 22 | 6 | adantrl 394 |
. . . . . . . . . 10
  Grp      inv        Id    |
| 23 | 22 | opreq1d 3975 |
. . . . . . . . 9
  Grp       inv            Id       |
| 24 | 9 | adantrl 394 |
. . . . . . . . . . 11
  Grp     inv       |
| 25 | | simprr 415 |
. . . . . . . . . . 11
  Grp      |
| 26 | | simprl 414 |
. . . . . . . . . . 11
  Grp      |
| 27 | 24, 25, 26 | 3jca 819 |
. . . . . . . . . 10
  Grp      inv        |
| 28 | 3 | grpass 8047 |
. . . . . . . . . 10
  Grp   inv    
     inv             inv              |
| 29 | 27, 28 | syldan 467 |
. . . . . . . . 9
  Grp       inv             inv              |
| 30 | 3, 4 | grplid 8061 |
. . . . . . . . . 10
  Grp
  Id       |
| 31 | 30 | adantrr 395 |
. . . . . . . . 9
  Grp     Id       |
| 32 | 23, 29, 31 | 3eqtr3d 1515 |
. . . . . . . 8
  Grp      inv              |
| 33 | 32 | adantlr 393 |
. . . . . . 7
   Grp


    inv              |
| 34 | 33 | adantr 389 |
. . . . . 6
    Grp  
             inv              |
| 35 | 2, 21, 34 | 3eqtr3d 1515 |
. . . . 5
    Grp  
             |
| 36 | 35 | ex 373 |
. . . 4
   Grp


              |
| 37 | 36 | exp43 384 |
. . 3
 Grp

                 |
| 38 | 37 | 3imp2 848 |
. 2
  Grp                |
| 39 | | opreq2 3969 |
. 2
           |
| 40 | 38, 39 | impbid1 517 |
1
  Grp                |