| Step | Hyp | Ref
| Expression |
| 1 | | euotd.1 |
. . . 4
   |
| 2 | | euotd.2 |
. . . 4
   |
| 3 | | euotd.3 |
. . . 4
   |
| 4 | | otexg 3967 |
. . . 4
 
   
   |
| 5 | 1, 2, 3, 4 | syl3anc 1135 |
. . 3
       |
| 6 | | euotd.4 |
. . . . . . . . . . . . 13
 

    |
| 7 | 6 | biimpa 280 |
. . . . . . . . . . . 12
 
     |
| 8 | | vex 2560 |
. . . . . . . . . . . . 13
 |
| 9 | | vex 2560 |
. . . . . . . . . . . . 13
 |
| 10 | | vex 2560 |
. . . . . . . . . . . . 13
 |
| 11 | 8, 9, 10 | otth 3979 |
. . . . . . . . . . . 12
    
        |
| 12 | 7, 11 | sylibr 137 |
. . . . . . . . . . 11
 
    
      |
| 13 | 12 | eqeq2d 2051 |
. . . . . . . . . 10
 
        
    |
| 14 | 13 | biimpd 132 |
. . . . . . . . 9
 
             |
| 15 | 14 | impancom 247 |
. . . . . . . 8
 
             |
| 16 | 15 | expimpd 345 |
. . . . . . 7
      
   
    |
| 17 | 16 | exlimdv 1700 |
. . . . . 6
         
  
    |
| 18 | 17 | exlimdvv 1777 |
. . . . 5
             
  
    |
| 19 | | tru 1247 |
. . . . . . . . . . 11
 |
| 20 | 2 | adantr 261 |
. . . . . . . . . . . . 13
 
   |
| 21 | 3 | ad2antrr 457 |
. . . . . . . . . . . . . 14
       |
| 22 | | simpr 103 |
. . . . . . . . . . . . . . . . . . 19
 

      |
| 23 | 22, 11 | sylibr 137 |
. . . . . . . . . . . . . . . . . 18
 

     
      |
| 24 | 23 | eqcomd 2045 |
. . . . . . . . . . . . . . . . 17
 

            |
| 25 | 6 | biimpar 281 |
. . . . . . . . . . . . . . . . 17
 

    |
| 26 | 24, 25 | jca 290 |
. . . . . . . . . . . . . . . 16
 

      
       |
| 27 | | a1tru 1259 |
. . . . . . . . . . . . . . . 16
 

   |
| 28 | 26, 27 | 2thd 164 |
. . . . . . . . . . . . . . 15
 

      
    
   |
| 29 | 28 | 3anassrs 1126 |
. . . . . . . . . . . . . 14
   


      
    
  |
| 30 | 21, 29 | sbcied 2799 |
. . . . . . . . . . . . 13
      
 ![]. ].](_drbrack.gif)     
    
  |
| 31 | 20, 30 | sbcied 2799 |
. . . . . . . . . . . 12
 
  
 ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)     
    
  |
| 32 | 1, 31 | sbcied 2799 |
. . . . . . . . . . 11
    ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)    
    
   |
| 33 | 19, 32 | mpbiri 157 |
. . . . . . . . . 10
   ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)     
       |
| 34 | 33 | spesbcd 2844 |
. . . . . . . . 9
     ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)             |
| 35 | | nfcv 2178 |
. . . . . . . . . 10
   |
| 36 | | nfsbc1v 2782 |
. . . . . . . . . . 11
    ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)     
      |
| 37 | 36 | nfex 1528 |
. . . . . . . . . 10
      ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)            |
| 38 | | sbceq1a 2773 |
. . . . . . . . . . 11
  
 ![]. ].](_drbrack.gif)     
    
  ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)    
    
    |
| 39 | 38 | exbidv 1706 |
. . . . . . . . . 10
      ![]. ].](_drbrack.gif)    
    
     ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)    
    
    |
| 40 | 35, 37, 39 | spcegf 2636 |
. . . . . . . . 9
      ![]. ].](_drbrack.gif)   ![]. ].](_drbrack.gif)    
    
     
 ![]. ].](_drbrack.gif)     
        |
| 41 | 2, 34, 40 | sylc 56 |
. . . . . . . 8
     
 ![]. ].](_drbrack.gif)     
       |
| 42 | | nfcv 2178 |
. . . . . . . . 9
   |
| 43 | | nfsbc1v 2782 |
. . . . . . . . . . 11
    ![]. ].](_drbrack.gif)     
      |
| 44 | 43 | nfex 1528 |
. . . . . . . . . 10
      ![]. ].](_drbrack.gif)            |
| 45 | 44 | nfex 1528 |
. . . . . . . . 9
      
 ![]. ].](_drbrack.gif)     
      |
| 46 | | sbceq1a 2773 |
. . . . . . . . . 10
      
    
  ![]. ].](_drbrack.gif)    
    
    |
| 47 | 46 | 2exbidv 1748 |
. . . . . . . . 9
               
      ![]. ].](_drbrack.gif)    
    
    |
| 48 | 42, 45, 47 | spcegf 2636 |
. . . . . . . 8
        ![]. ].](_drbrack.gif)                    
    
    |
| 49 | 3, 41, 48 | sylc 56 |
. . . . . . 7
          
    
   |
| 50 | | excom13 1579 |
. . . . . . 7
          
    
          
    
   |
| 51 | 49, 50 | sylib 127 |
. . . . . 6
          
    
   |
| 52 | | eqeq1 2046 |
. . . . . . . 8
    
    
  
        |
| 53 | 52 | anbi1d 438 |
. . . . . . 7
    
      
             |
| 54 | 53 | 3exbidv 1749 |
. . . . . 6
    
           
          
    
    |
| 55 | 51, 54 | syl5ibrcom 146 |
. . . . 5
                
    |
| 56 | 18, 55 | impbid 120 |
. . . 4
             
       |
| 57 | 56 | alrimiv 1754 |
. . 3
              
        |
| 58 | | eqeq2 2049 |
. . . . . 6
    

       |
| 59 | 58 | bibi2d 221 |
. . . . 5
    
            
 
            
        |
| 60 | 59 | albidv 1705 |
. . . 4
    
               

              
        |
| 61 | 60 | spcegv 2641 |
. . 3
  
                
                      
    |
| 62 | 5, 57, 61 | sylc 56 |
. 2
                 
   |
| 63 | | df-eu 1903 |
. 2
              
                
   |
| 64 | 62, 63 | sylibr 137 |
1
                 |