Proof of Theorem mapdiscnlem
| Step | Hyp | Ref
| Expression |
| 1 | | mapdiscn.3 |
. . 3
 |
| 2 | 1 | distop 8919 |
. 2
 Top |
| 3 | | unipw 3504 |
. . . . . . . 8
   |
| 4 | 3 | eqcomi 1888 |
. . . . . . 7
   |
| 5 | | mapdiscn.2 |
. . . . . . 7
  |
| 6 | | feq23 4554 |
. . . . . . 7
   
      
          |
| 7 | 4, 5, 6 | mp2an 761 |
. . . . . 6
              |
| 8 | 7 | biimpi 168 |
. . . . 5
              |
| 9 | 8 | adantl 424 |
. . . 4
    Top Top               |
| 10 | | imassrn 4278 |
. . . . . . 7
      |
| 11 | | dfdm4 4151 |
. . . . . . . . . 10
 |
| 12 | 11 | eqcomi 1888 |
. . . . . . . . 9
 |
| 13 | 12 | sseq2i 2642 |
. . . . . . . 8
     
       |
| 14 | | fdm 4567 |
. . . . . . . . . . 11
    
  |
| 15 | | sseq2 2639 |
. . . . . . . . . . . . 13

     
        |
| 16 | 15 | biimpd 170 |
. . . . . . . . . . . 12

     
        |
| 17 | | fex 4595 |
. . . . . . . . . . . . . . . 16
     
   |
| 18 | 1, 17 | mpan2 760 |
. . . . . . . . . . . . . . 15
       |
| 19 | | cnvexg 4424 |
. . . . . . . . . . . . . . 15

   |
| 20 | 18, 19 | syl 12 |
. . . . . . . . . . . . . 14
     
  |
| 21 | | imaexg 4279 |
. . . . . . . . . . . . . 14
 
       |
| 22 | | elpwg 3038 |
. . . . . . . . . . . . . 14
                     |
| 23 | 20, 21, 22 | 3syl 24 |
. . . . . . . . . . . . 13
                    |
| 24 | 23 | biimprd 171 |
. . . . . . . . . . . 12
          
         |
| 25 | 16, 24 | syl9 71 |
. . . . . . . . . . 11

    
     
          |
| 26 | 14, 25 | mpcom 60 |
. . . . . . . . . 10
          
    
    |
| 27 | 26 | ad2antlr 441 |
. . . . . . . . 9
     Top Top
                     |
| 28 | 27 | com12 14 |
. . . . . . . 8
     
     Top Top                |
| 29 | 13, 28 | sylbi 216 |
. . . . . . 7
     
     Top Top
               |
| 30 | 10, 29 | ax-mp 7 |
. . . . . 6
     Top Top
              |
| 31 | 30 | ex 402 |
. . . . 5
    Top Top                |
| 32 | 31 | r19.21aiv 2175 |
. . . 4
    Top Top               |
| 33 | 9, 32 | jca 310 |
. . 3
    Top Top                        |
| 34 | | eqid 1884 |
. . . . 5
     |
| 35 | | eqid 1884 |
. . . . 5
   |
| 36 | 34, 35 | iscn 9034 |
. . . 4
   Top
Top    Cn                     |
| 37 | 36 | adantr 425 |
. . 3
    Top Top         Cn                     |
| 38 | 33, 37 | mpbird 213 |
. 2
    Top Top        Cn    |
| 39 | 2, 38 | mpanl1 770 |
1
  Top        Cn    |