Proof of Theorem fdc1
| Step | Hyp | Ref
| Expression |
| 1 | | fdc1.9 |
. 2


  |
| 2 | | eleq1 1957 |
. . . . . . . 8
     |
| 3 | 2 | anbi2d 678 |
. . . . . . 7
  
 
    |
| 4 | | sbequ12r 1546 |
. . . . . . 7
    ![]](rbrack.gif)    |
| 5 | 3, 4 | anbi12d 690 |
. . . . . 6
       ![]](rbrack.gif)   
     |
| 6 | 5 | imbi1d 675 |
. . . . 5
        ![]](rbrack.gif)  
           
           
  
           
            |
| 7 | | fdc1.1 |
. . . . . . . 8
 |
| 8 | | fdc1.2 |
. . . . . . . 8
 |
| 9 | | fdc1.3 |
. . . . . . . 8
     |
| 10 | | fdc1.4 |
. . . . . . . 8
   |
| 11 | | ax-17 1317 |
. . . . . . . . 9

    |
| 12 | | fdc1.6 |
. . . . . . . . 9
           |
| 13 | 11, 12 | sbhypf 2452 |
. . . . . . . 8
          ![]](rbrack.gif)    |
| 14 | | fdc1.7 |
. . . . . . . 8
         |
| 15 | | ax-17 1317 |
. . . . . . . . 9

    |
| 16 | | fdc1.8 |
. . . . . . . . 9
         |
| 17 | 15, 16 | sbhypf 2452 |
. . . . . . . 8
        ![]](rbrack.gif)    |
| 18 | | simprl 450 |
. . . . . . . 8
     ![]](rbrack.gif)     |
| 19 | | fdc1.10 |
. . . . . . . . 9

  |
| 20 | 19 | adantr 425 |
. . . . . . . 8
     ![]](rbrack.gif)     |
| 21 | | ax-17 1317 |
. . . . . . . . . . 11
     
   |
| 22 | | ax-17 1317 |
. . . . . . . . . . . . 13

    |
| 23 | 22 | hbsb3 1575 |
. . . . . . . . . . . 12
   ![]](rbrack.gif)
    ![]](rbrack.gif)   |
| 24 | | ax-17 1317 |
. . . . . . . . . . . . 13
    |
| 25 | | ax-17 1317 |
. . . . . . . . . . . . . 14

    |
| 26 | 25 | hbsb3 1575 |
. . . . . . . . . . . . 13
   ![]](rbrack.gif)
    ![]](rbrack.gif)   |
| 27 | 24, 26 | hbrex 2149 |
. . . . . . . . . . . 12
    ![]](rbrack.gif)
     ![]](rbrack.gif)   |
| 28 | 23, 27 | hbor 1355 |
. . . . . . . . . . 11
    ![]](rbrack.gif) 
  ![]](rbrack.gif)       ![]](rbrack.gif)    ![]](rbrack.gif)    |
| 29 | 21, 28 | hbim 1354 |
. . . . . . . . . 10
  
    ![]](rbrack.gif) 
  ![]](rbrack.gif)           ![]](rbrack.gif)

  ![]](rbrack.gif)     |
| 30 | | eleq1 1957 |
. . . . . . . . . . . 12
     |
| 31 | 30 | anbi2d 678 |
. . . . . . . . . . 11
  
 
    |
| 32 | | sbequ12 1545 |
. . . . . . . . . . . 12
    ![]](rbrack.gif)    |
| 33 | | sbequ12 1545 |
. . . . . . . . . . . . 13
    ![]](rbrack.gif)    |
| 34 | 33 | rexbidv 2124 |
. . . . . . . . . . . 12
      ![]](rbrack.gif)    |
| 35 | 32, 34 | orbi12d 689 |
. . . . . . . . . . 11
        ![]](rbrack.gif)    ![]](rbrack.gif)     |
| 36 | 31, 35 | imbi12d 688 |
. . . . . . . . . 10
          
    ![]](rbrack.gif) 
  ![]](rbrack.gif)      |
| 37 | | fdc1.11 |
. . . . . . . . . 10
   

   |
| 38 | 29, 36, 37 | chvar 1530 |
. . . . . . . . 9
      ![]](rbrack.gif)

  ![]](rbrack.gif)    |
| 39 | 38 | adantlr 429 |
. . . . . . . 8
      ![]](rbrack.gif)       ![]](rbrack.gif)    ![]](rbrack.gif)    |
| 40 | | ax-17 1317 |
. . . . . . . . . . . . 13

    |
| 41 | 40, 26 | hban 1356 |
. . . . . . . . . . . 12
    ![]](rbrack.gif)       ![]](rbrack.gif)    |
| 42 | | ax-17 1317 |
. . . . . . . . . . . 12
         |
| 43 | 41, 42 | hban 1356 |
. . . . . . . . . . 11
     ![]](rbrack.gif)  
        ![]](rbrack.gif)  
    |
| 44 | | ax-17 1317 |
. . . . . . . . . . 11
        |
| 45 | 43, 44 | hbim 1354 |
. . . . . . . . . 10
      ![]](rbrack.gif)               ![]](rbrack.gif)  
       |
| 46 | 33 | anbi2d 678 |
. . . . . . . . . . . 12
       ![]](rbrack.gif)     |
| 47 | 30 | anbi1d 679 |
. . . . . . . . . . . 12
         |
| 48 | 46, 47 | anbi12d 690 |
. . . . . . . . . . 11
            ![]](rbrack.gif) 
      |
| 49 | | breq2 3342 |
. . . . . . . . . . 11
         |
| 50 | 48, 49 | imbi12d 688 |
. . . . . . . . . 10
                 ![]](rbrack.gif)           |
| 51 | | fdc1.12 |
. . . . . . . . . 10
           |
| 52 | 45, 50, 51 | chvar 1530 |
. . . . . . . . 9
     ![]](rbrack.gif)  
      |
| 53 | 52 | adantllr 433 |
. . . . . . . 8
       ![]](rbrack.gif)     ![]](rbrack.gif)  
      |
| 54 | 7, 8, 9, 10, 13, 14, 17, 18, 20, 39, 53 | fdc 15812 |
. . . . . . 7
     ![]](rbrack.gif)                              |
| 55 | 54 | anassrs 489 |
. . . . . 6
  
   ![]](rbrack.gif)  
                 
        |
| 56 | | idd 75 |
. . . . . . . . 9
  
   ![]](rbrack.gif)          
           |
| 57 | | dfsbcq 2455 |
. . . . . . . . . . . . 13
            ![]](rbrack.gif)   ![]](rbrack.gif)    |
| 58 | | fvex 4689 |
. . . . . . . . . . . . . 14
     |
| 59 | | fdc1.5 |
. . . . . . . . . . . . . 14
         |
| 60 | 58, 59 | sbcie 2485 |
. . . . . . . . . . . . 13
       ![]](rbrack.gif)
  |
| 61 | 57, 60 | syl5rbbr 594 |
. . . . . . . . . . . 12
        ![]](rbrack.gif)    |
| 62 | 61 | biimpcd 172 |
. . . . . . . . . . 11
   ![]](rbrack.gif)
        |
| 63 | 62 | adantl 424 |
. . . . . . . . . 10
  
   ![]](rbrack.gif)          |
| 64 | 63 | anim1d 619 |
. . . . . . . . 9
  
   ![]](rbrack.gif)              |
| 65 | | idd 75 |
. . . . . . . . 9
  
   ![]](rbrack.gif)                  |
| 66 | 56, 64, 65 | 3anim123d 1175 |
. . . . . . . 8
  
   ![]](rbrack.gif)           
      
               

          |
| 67 | 66 | eximdv 1669 |
. . . . . . 7
  
   ![]](rbrack.gif)                                      
           |
| 68 | 67 | reximdv 2202 |
. . . . . 6
  
   ![]](rbrack.gif)                            
           
           |
| 69 | 55, 68 | mpd 29 |
. . . . 5
  
   ![]](rbrack.gif)  
           
          |
| 70 | 6, 69 | chvarv 1712 |
. . . 4
  
  
           
          |
| 71 | 70 | ex 402 |
. . 3
   

          

           |
| 72 | 71 | r19.23adva 2216 |
. 2

 
            

          |
| 73 | 1, 72 | mpd 29 |
1


          

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