| Step | Hyp | Ref
| Expression |
| 1 | | eleq1 2259 |
. . . . . . . . 9
        

           |
| 2 | 1 | dcbid 839 |
. . . . . . . 8
        
DECID
DECID            |
| 3 | | ctiunct.sdc |
. . . . . . . . 9
  DECID   |
| 4 | 3 | adantr 276 |
. . . . . . . 8
 

 DECID   |
| 5 | | ctiunct.j |
. . . . . . . . . . . 12
         |
| 6 | 5 | adantr 276 |
. . . . . . . . . . 11
 

        |
| 7 | | f1of 5507 |
. . . . . . . . . . 11
               |
| 8 | 6, 7 | syl 14 |
. . . . . . . . . 10
 

        |
| 9 | | simpr 110 |
. . . . . . . . . 10
 

  |
| 10 | 8, 9 | ffvelcdmd 5701 |
. . . . . . . . 9
 

        |
| 11 | | xp1st 6232 |
. . . . . . . . 9
      
          |
| 12 | 10, 11 | syl 14 |
. . . . . . . 8
 

          |
| 13 | 2, 4, 12 | rspcdva 2873 |
. . . . . . 7
 

DECID           |
| 14 | 13 | adantr 276 |
. . . . . 6
            
DECID           |
| 15 | | eleq1 2259 |
. . . . . . . 8
        
               ![]_ ]_](_urbrack.gif)                       ![]_ ]_](_urbrack.gif)    |
| 16 | 15 | dcbid 839 |
. . . . . . 7
        
DECID
              ![]_ ]_](_urbrack.gif) DECID                       ![]_ ]_](_urbrack.gif)    |
| 17 | | ctiunct.f |
. . . . . . . . . . 11
       |
| 18 | | fof 5483 |
. . . . . . . . . . 11
           |
| 19 | 17, 18 | syl 14 |
. . . . . . . . . 10
       |
| 20 | 19 | ad2antrr 488 |
. . . . . . . . 9
                   |
| 21 | | simpr 110 |
. . . . . . . . 9
                       |
| 22 | 20, 21 | ffvelcdmd 5701 |
. . . . . . . 8
                           |
| 23 | | ctiunct.tdc |
. . . . . . . . . 10
 
  DECID   |
| 24 | 23 | ralrimiva 2570 |
. . . . . . . . 9
  
DECID   |
| 25 | 24 | ad2antrr 488 |
. . . . . . . 8
             
 DECID   |
| 26 | | nfcv 2339 |
. . . . . . . . . 10
   |
| 27 | | nfcsb1v 3117 |
. . . . . . . . . . . 12
                ![]_ ]_](_urbrack.gif)  |
| 28 | 27 | nfcri 2333 |
. . . . . . . . . . 11

              ![]_ ]_](_urbrack.gif)  |
| 29 | 28 | nfdc 1673 |
. . . . . . . . . 10
 DECID               ![]_ ]_](_urbrack.gif)  |
| 30 | 26, 29 | nfralya 2537 |
. . . . . . . . 9
  
DECID               ![]_ ]_](_urbrack.gif)  |
| 31 | | csbeq1a 3093 |
. . . . . . . . . . . 12
            
              ![]_ ]_](_urbrack.gif)   |
| 32 | 31 | eleq2d 2266 |
. . . . . . . . . . 11
            

              ![]_ ]_](_urbrack.gif)    |
| 33 | 32 | dcbid 839 |
. . . . . . . . . 10
            
DECID
DECID               ![]_ ]_](_urbrack.gif)    |
| 34 | 33 | ralbidv 2497 |
. . . . . . . . 9
            
 
DECID
 DECID
              ![]_ ]_](_urbrack.gif)    |
| 35 | 30, 34 | rspc 2862 |
. . . . . . . 8
            
 

DECID
 DECID               ![]_ ]_](_urbrack.gif)    |
| 36 | 22, 25, 35 | sylc 62 |
. . . . . . 7
              DECID               ![]_ ]_](_urbrack.gif)   |
| 37 | 10 | adantr 276 |
. . . . . . . 8
                     |
| 38 | | xp2nd 6233 |
. . . . . . . 8
      
          |
| 39 | 37, 38 | syl 14 |
. . . . . . 7
                       |
| 40 | 16, 36, 39 | rspcdva 2873 |
. . . . . 6
            
DECID                       ![]_ ]_](_urbrack.gif)   |
| 41 | | dcan2 936 |
. . . . . 6
DECID         DECID                       ![]_ ]_](_urbrack.gif)
DECID                                ![]_ ]_](_urbrack.gif)     |
| 42 | 14, 40, 41 | sylc 62 |
. . . . 5
            
DECID                                ![]_ ]_](_urbrack.gif)    |
| 43 | | simpr 110 |
. . . . . . . 8
                       |
| 44 | 43 | intnanrd 933 |
. . . . . . 7
                                            ![]_ ]_](_urbrack.gif)    |
| 45 | 44 | olcd 735 |
. . . . . 6
                                             ![]_ ]_](_urbrack.gif)                                 ![]_ ]_](_urbrack.gif)     |
| 46 | | df-dc 836 |
. . . . . 6
DECID                                ![]_ ]_](_urbrack.gif) 
                                ![]_ ]_](_urbrack.gif)                                 ![]_ ]_](_urbrack.gif)     |
| 47 | 45, 46 | sylibr 134 |
. . . . 5
             DECID                                ![]_ ]_](_urbrack.gif)    |
| 48 | | exmiddc 837 |
. . . . . 6
DECID                             |
| 49 | 13, 48 | syl 14 |
. . . . 5
 

                    |
| 50 | 42, 47, 49 | mpjaodan 799 |
. . . 4
 

DECID                                ![]_ ]_](_urbrack.gif)    |
| 51 | | 2fveq3 5566 |
. . . . . . . . 9
                   |
| 52 | 51 | eleq1d 2265 |
. . . . . . . 8
         
           |
| 53 | | 2fveq3 5566 |
. . . . . . . . 9
                   |
| 54 | 51 | fveq2d 5565 |
. . . . . . . . . 10
                           |
| 55 | 54 | csbeq1d 3091 |
. . . . . . . . 9
               ![]_ ]_](_urbrack.gif)               ![]_ ]_](_urbrack.gif)   |
| 56 | 53, 55 | eleq12d 2267 |
. . . . . . . 8
                        ![]_ ]_](_urbrack.gif)
                      ![]_ ]_](_urbrack.gif)    |
| 57 | 52, 56 | anbi12d 473 |
. . . . . . 7
                                 ![]_ ]_](_urbrack.gif) 
                               ![]_ ]_](_urbrack.gif)     |
| 58 | | ctiunct.u |
. . . . . . 7
                                ![]_ ]_](_urbrack.gif)    |
| 59 | 57, 58 | elrab2 2923 |
. . . . . 6

                                ![]_ ]_](_urbrack.gif)     |
| 60 | | ibar 301 |
. . . . . . 7
                                 ![]_ ]_](_urbrack.gif) 
                                ![]_ ]_](_urbrack.gif)      |
| 61 | 60 | adantl 277 |
. . . . . 6
 

                                ![]_ ]_](_urbrack.gif) 
                                ![]_ ]_](_urbrack.gif)      |
| 62 | 59, 61 | bitr4id 199 |
. . . . 5
 


                               ![]_ ]_](_urbrack.gif)     |
| 63 | 62 | dcbid 839 |
. . . 4
 

DECID
DECID                                ![]_ ]_](_urbrack.gif)     |
| 64 | 50, 63 | mpbird 167 |
. . 3
 

DECID
  |
| 65 | 64 | ralrimiva 2570 |
. 2
  DECID   |
| 66 | | eleq1 2259 |
. . . 4
 
   |
| 67 | 66 | dcbid 839 |
. . 3
 DECID
DECID
   |
| 68 | 67 | cbvralv 2729 |
. 2
 
DECID
 DECID
  |
| 69 | 65, 68 | sylib 122 |
1
  DECID   |