| Step | Hyp | Ref
 | Expression | 
| 1 |   | nchoicelem1 6290 | 
. . . 4
       Nn           Tc     1c   | 
| 2 |   | nchoicelem2 6291 | 
. . . 4
       Nn           Tc     2c   | 
| 3 |   | ioran 476 | 
. . . 4
            Tc     1c     
    Tc     2c              Tc     1c           
Tc     2c    | 
| 4 | 1, 2, 3 | sylanbrc 645 | 
. . 3
       Nn            Tc     1c          Tc     2c    | 
| 5 | 4 | nrex 2717 | 
. 2
        
Nn        Tc     1c     
    Tc     2c   | 
| 6 |   | nchoicelem19 6308 | 
. . 3
     c We
NC        NC    Spac       Fin   Tc         | 
| 7 |   | finnc 6244 | 
. . . . . . . 8
     Spac
      Fin   Nc
  Spac       Nn   | 
| 8 | 7 | biimpi 186 | 
. . . . . . 7
     Spac
      Fin   Nc   Spac       Nn   | 
| 9 | 8 | ad2antrl 708 | 
. . . . . 6
       c We NC       NC        Spac
      Fin   Tc           Nc   Spac       Nn   | 
| 10 |   | simpll 730 | 
. . . . . . . . 9
       c We NC       NC        Spac
      Fin   Tc            c We NC   | 
| 11 |   | simplr 731 | 
. . . . . . . . 9
       c We NC       NC        Spac
      Fin   Tc              
NC   | 
| 12 |   | simprl 732 | 
. . . . . . . . 9
       c We NC       NC        Spac
      Fin   Tc             Spac      
Fin   | 
| 13 |   | nchoicelem17 6306 | 
. . . . . . . . 9
      c We NC       NC     Spac       Fin        Spac
  Tc   
  Fin     Nc   Spac   Tc   
    Tc Nc   Spac      
1c 
  Nc   Spac   Tc   
    Tc Nc   Spac      
2c     | 
| 14 | 10, 11, 12, 13 | syl3anc 1182 | 
. . . . . . . 8
       c We NC       NC        Spac
      Fin   Tc             
Spac   Tc      Fin     Nc   Spac   Tc   
    Tc Nc   Spac      
1c 
  Nc   Spac   Tc   
    Tc Nc   Spac      
2c     | 
| 15 | 14 | simprd 449 | 
. . . . . . 7
       c We NC       NC        Spac
      Fin   Tc             Nc   Spac
  Tc   
    Tc Nc   Spac      
1c 
  Nc   Spac   Tc   
    Tc Nc   Spac      
2c    | 
| 16 |   | simprr 733 | 
. . . . . . . . . . 11
       c We NC       NC        Spac
      Fin   Tc           Tc
       | 
| 17 | 16 | fveq2d 5333 | 
. . . . . . . . . 10
       c We NC       NC        Spac
      Fin   Tc             Spac   Tc   
    Spac      | 
| 18 | 17 | nceqd 6111 | 
. . . . . . . . 9
       c We NC       NC        Spac
      Fin   Tc           Nc   Spac   Tc      Nc   Spac      | 
| 19 | 18 | eqeq1d 2361 | 
. . . . . . . 8
       c We NC       NC        Spac
      Fin   Tc             Nc   Spac
  Tc   
    Tc Nc   Spac      
1c 
 
Nc   Spac    
    Tc Nc   Spac      
1c    | 
| 20 | 18 | eqeq1d 2361 | 
. . . . . . . 8
       c We NC       NC        Spac
      Fin   Tc             Nc   Spac
  Tc   
    Tc Nc   Spac      
2c 
 
Nc   Spac    
    Tc Nc   Spac      
2c    | 
| 21 | 19, 20 | orbi12d 690 | 
. . . . . . 7
       c We NC       NC        Spac
      Fin   Tc             
Nc   Spac   Tc   
    Tc Nc   Spac      
1c 
  Nc   Spac   Tc   
    Tc Nc   Spac      
2c       Nc   Spac    
    Tc Nc   Spac      
1c 
  Nc   Spac    
    Tc Nc   Spac      
2c     | 
| 22 | 15, 21 | mpbid 201 | 
. . . . . 6
       c We NC       NC        Spac
      Fin   Tc             Nc   Spac
        Tc Nc   Spac      
1c 
  Nc   Spac    
    Tc Nc   Spac      
2c    | 
| 23 |   | id 19 | 
. . . . . . . . 9
       Nc   Spac           Nc   Spac      | 
| 24 |   | tceq 6159 | 
. . . . . . . . . 10
       Nc   Spac       Tc     Tc Nc   Spac      | 
| 25 | 24 | addceq1d 4390 | 
. . . . . . . . 9
       Nc   Spac         Tc     1c      Tc Nc   Spac      
1c   | 
| 26 | 23, 25 | eqeq12d 2367 | 
. . . . . . . 8
       Nc   Spac              Tc     1c    Nc   Spac         Tc Nc   Spac    
 
1c    | 
| 27 | 24 | addceq1d 4390 | 
. . . . . . . . 9
       Nc   Spac         Tc     2c      Tc Nc   Spac      
2c   | 
| 28 | 23, 27 | eqeq12d 2367 | 
. . . . . . . 8
       Nc   Spac              Tc     2c    Nc   Spac         Tc Nc   Spac    
 
2c    | 
| 29 | 26, 28 | orbi12d 690 | 
. . . . . . 7
       Nc   Spac               Tc     1c          Tc     2c  
 
  Nc   Spac    
    Tc Nc   Spac      
1c 
  Nc   Spac    
    Tc Nc   Spac      
2c     | 
| 30 | 29 | rspcev 2956 | 
. . . . . 6
     Nc   Spac       Nn     Nc   Spac    
    Tc Nc   Spac      
1c 
  Nc   Spac    
    Tc Nc   Spac      
2c        
  Nn        Tc     1c     
    Tc     2c    | 
| 31 | 9, 22, 30 | syl2anc 642 | 
. . . . 5
       c We NC       NC        Spac
      Fin   Tc             
  Nn        Tc     1c     
    Tc     2c    | 
| 32 | 31 | ex 423 | 
. . . 4
      c We NC       NC         Spac    
  Fin   Tc              
Nn        Tc     1c     
    Tc     2c     | 
| 33 | 32 | rexlimdva 2739 | 
. . 3
     c We
NC         NC    Spac
      Fin   Tc              
Nn        Tc     1c     
    Tc     2c     | 
| 34 | 6, 33 | mpd 14 | 
. 2
     c We
NC        Nn        Tc     1c     
    Tc     2c    | 
| 35 | 5, 34 | mto 167 | 
1
     c We NC |