| Step | Hyp | Ref
 | Expression | 
| 1 |   | fnpw1fn 5854 | 
. 2
  Pw1Fn   1c | 
| 2 |   | df-pw1fn 5767 | 
. . . 4
  Pw1Fn        1c    1     | 
| 3 | 2 | rnmpt 5687 | 
. . 3
    Pw1Fn          
  1c
     1     | 
| 4 |   | vex 2863 | 
. . . . . . 7
        | 
| 5 | 4 | sspw1 4336 | 
. . . . . 6
        1           
         1     | 
| 6 |   | df1c2 4169 | 
. . . . . . 7
 
1c  
 1   | 
| 7 | 6 | sseq2i 3297 | 
. . . . . 6
       1c        1    | 
| 8 |   | ssv 3292 | 
. . . . . . . 8
        | 
| 9 | 8 | biantrur 492 | 
. . . . . . 7
        1  
 
              1     | 
| 10 | 9 | exbii 1582 | 
. . . . . 6
       
   1                     1     | 
| 11 | 5, 7, 10 | 3bitr4i 268 | 
. . . . 5
       1c           1    | 
| 12 | 4 | elpw 3729 | 
. . . . 5
        1c      
1c  | 
| 13 |   | df-rex 2621 | 
. . . . . 6
       
1c  
   1             1c    
   1      | 
| 14 |   | el1c 4140 | 
. . . . . . . . 9
       1c     
         | 
| 15 | 14 | anbi1i 676 | 
. . . . . . . 8
       
1c        1    
 
     
             1      | 
| 16 |   | 19.41v 1901 | 
. . . . . . . 8
                     1            
             1      | 
| 17 | 15, 16 | bitr4i 243 | 
. . . . . . 7
       
1c        1    
 
    
             1      | 
| 18 | 17 | exbii 1582 | 
. . . . . 6
          1c        1                           1      | 
| 19 |   | excom 1741 | 
. . . . . . 7
                   
   1    
 
                    1      | 
| 20 |   | snex 4112 | 
. . . . . . . . 9
       
  | 
| 21 |   | unieq 3901 | 
. . . . . . . . . . . 12
                        | 
| 22 |   | vex 2863 | 
. . . . . . . . . . . . 13
        | 
| 23 | 22 | unisn 3908 | 
. . . . . . . . . . . 12
           | 
| 24 | 21, 23 | syl6eq 2401 | 
. . . . . . . . . . 11
                     | 
| 25 |   | pw1eq 4144 | 
. . . . . . . . . . 11
       
     1       1    | 
| 26 | 24, 25 | syl 15 | 
. . . . . . . . . 10
              1       1    | 
| 27 | 26 | eqeq2d 2364 | 
. . . . . . . . 9
                   1           1     | 
| 28 | 20, 27 | ceqsexv 2895 | 
. . . . . . . 8
                     1            1    | 
| 29 | 28 | exbii 1582 | 
. . . . . . 7
                   
   1    
 
      
 1    | 
| 30 | 19, 29 | bitri 240 | 
. . . . . 6
                   
   1    
 
      
 1    | 
| 31 | 13, 18, 30 | 3bitri 262 | 
. . . . 5
       
1c  
   1              1    | 
| 32 | 11, 12, 31 | 3bitr4i 268 | 
. . . 4
        1c        1c      1     | 
| 33 | 32 | eqabi 2465 | 
. . 3
   1c
      
     1c    
 1     | 
| 34 | 3, 33 | eqtr4i 2376 | 
. 2
    Pw1Fn    1c | 
| 35 |   | el1c 4140 | 
. . . . . 6
       1c     
         | 
| 36 |   | el1c 4140 | 
. . . . . 6
       1c     
         | 
| 37 | 35, 36 | anbi12i 678 | 
. . . . 5
       
1c       1c         
              
      | 
| 38 |   | eeanv 1913 | 
. . . . 5
                   
              
              
      | 
| 39 | 37, 38 | bitr4i 243 | 
. . . 4
       
1c       1c                             | 
| 40 |   | pw111 4171 | 
. . . . . . . 8
    1    
 1            | 
| 41 | 40 | biimpi 186 | 
. . . . . . 7
    1    
 1        
   | 
| 42 | 41 | a1i 10 | 
. . . . . 6
                           1      1        
    | 
| 43 |   | fveq2 5329 | 
. . . . . . . 8
               Pw1Fn         Pw1Fn        | 
| 44 |   | vex 2863 | 
. . . . . . . . 9
        | 
| 45 | 44 | pw1fnval 5852 | 
. . . . . . . 8
    Pw1Fn        
 1   | 
| 46 | 43, 45 | syl6eq 2401 | 
. . . . . . 7
               Pw1Fn        1    | 
| 47 |   | fveq2 5329 | 
. . . . . . . 8
               Pw1Fn         Pw1Fn        | 
| 48 |   | vex 2863 | 
. . . . . . . . 9
        | 
| 49 | 48 | pw1fnval 5852 | 
. . . . . . . 8
    Pw1Fn        
 1   | 
| 50 | 47, 49 | syl6eq 2401 | 
. . . . . . 7
               Pw1Fn        1    | 
| 51 | 46, 50 | eqeqan12d 2368 | 
. . . . . 6
                            Pw1Fn    
    Pw1Fn        1  
   1     | 
| 52 |   | eqeq12 2365 | 
. . . . . . 7
                             
         
      | 
| 53 | 44 | sneqb 3877 | 
. . . . . . 7
                      | 
| 54 | 52, 53 | syl6bb 252 | 
. . . . . 6
                             
            | 
| 55 | 42, 51, 54 | 3imtr4d 259 | 
. . . . 5
                            Pw1Fn    
    Pw1Fn               | 
| 56 | 55 | exlimivv 1635 | 
. . . 4
                   
            Pw1Fn    
    Pw1Fn               | 
| 57 | 39, 56 | sylbi 187 | 
. . 3
       
1c       1c      
Pw1Fn         Pw1Fn               | 
| 58 | 57 | rgen2a 2681 | 
. 2
       1c     
1c    Pw1Fn         Pw1Fn              | 
| 59 |   | dff1o6 5476 | 
. 2
    Pw1Fn  1c  1c     Pw1Fn   1c
    Pw1Fn    1c        1c      1c   
Pw1Fn         Pw1Fn                | 
| 60 | 1, 34, 58, 59 | mpbir3an 1134 | 
1
  Pw1Fn  1c  1c |