Proof of Theorem wwlksnextprop
| Step | Hyp | Ref
| Expression |
| 1 | | eqidd 2623 |
. . . . 5
        
 substr        substr         |
| 2 | | wwlksnextprop.x |
. . . . . . . . 9
   WWalksN
  |
| 3 | 2 | wwlksnextproplem1 26804 |
. . . . . . . 8
 
   substr                |
| 4 | 3 | ancoms 469 |
. . . . . . 7
 
   substr                |
| 5 | 4 | adantr 481 |
. . . . . 6
        
  substr                |
| 6 | | eqeq2 2633 |
. . . . . . 7
        substr                substr             |
| 7 | 6 | adantl 482 |
. . . . . 6
        
   substr
            
  substr             |
| 8 | 5, 7 | mpbid 222 |
. . . . 5
        
  substr            |
| 9 | | wwlksnextprop.e |
. . . . . . . 8
Edg   |
| 10 | 2, 9 | wwlksnextproplem2 26805 |
. . . . . . 7
 
 
lastS   substr         lastS      |
| 11 | 10 | ancoms 469 |
. . . . . 6
 
  lastS   substr         lastS      |
| 12 | 11 | adantr 481 |
. . . . 5
        
 lastS   substr         lastS      |
| 13 | | simpr 477 |
. . . . . . . 8
 
   |
| 14 | 13 | adantr 481 |
. . . . . . 7
        
  |
| 15 | | simpr 477 |
. . . . . . 7
        
      |
| 16 | | simpll 790 |
. . . . . . 7
        
  |
| 17 | | wwlksnextprop.y |
. . . . . . . 8
  WWalksN        |
| 18 | 2, 9, 17 | wwlksnextproplem3 26806 |
. . . . . . 7
     
  substr
        |
| 19 | 14, 15, 16, 18 | syl3anc 1326 |
. . . . . 6
        
 substr         |
| 20 | | eqeq2 2633 |
. . . . . . . 8
  substr         substr      
 substr        substr          |
| 21 | | fveq1 6190 |
. . . . . . . . 9
  substr             substr            |
| 22 | 21 | eqeq1d 2624 |
. . . . . . . 8
  substr              substr             |
| 23 | | fveq2 6191 |
. . . . . . . . . 10
  substr       lastS  
lastS   substr          |
| 24 | 23 | preq1d 4274 |
. . . . . . . . 9
  substr        lastS    lastS     lastS   substr         lastS      |
| 25 | 24 | eleq1d 2686 |
. . . . . . . 8
  substr         lastS    lastS     lastS   substr         lastS       |
| 26 | 20, 22, 25 | 3anbi123d 1399 |
. . . . . . 7
  substr          substr            lastS   
lastS       substr        substr         substr           lastS   substr         lastS        |
| 27 | 26 | adantl 482 |
. . . . . 6
   
       substr       
   substr
           lastS    lastS       substr        substr      
  substr           lastS   substr         lastS        |
| 28 | 19, 27 | rspcedv 3313 |
. . . . 5
        
   substr
       substr      
  substr
          lastS   substr         lastS     
  substr      
     lastS   
lastS        |
| 29 | 1, 8, 12, 28 | mp3and 1427 |
. . . 4
        

  substr      
     lastS   
lastS       |
| 30 | 29 | ex 450 |
. . 3
 
         substr      
   
 lastS    lastS        |
| 31 | 21 | eqcoms 2630 |
. . . . . . . . 9
  substr      
      substr            |
| 32 | 31 | eqeq1d 2624 |
. . . . . . . 8
  substr      
       substr             |
| 33 | 3 | eqcomd 2628 |
. . . . . . . . . . 11
 
       substr            |
| 34 | 33 | ancoms 469 |
. . . . . . . . . 10
 
       substr            |
| 35 | 34 | adantr 481 |
. . . . . . . . 9
    
      substr            |
| 36 | | eqeq2 2633 |
. . . . . . . . . 10
   substr                     substr             |
| 37 | 36 | eqcoms 2630 |
. . . . . . . . 9
   substr         
    
      substr             |
| 38 | 35, 37 | syl5ibr 236 |
. . . . . . . 8
   substr         
    
       |
| 39 | 32, 38 | syl6bi 243 |
. . . . . . 7
  substr      
       


        |
| 40 | 39 | imp 445 |
. . . . . 6
   substr      
       
         |
| 41 | 40 | 3adant3 1081 |
. . . . 5
   substr      
   
 lastS    lastS       
         |
| 42 | 41 | com12 32 |
. . . 4
    
   substr
           lastS    lastS    
       |
| 43 | 42 | rexlimdva 3031 |
. . 3
 
     substr            lastS   
lastS            |
| 44 | 30, 43 | impbid 202 |
. 2
 
      
  substr      
   
 lastS    lastS        |
| 45 | 44 | rabbidva 3188 |
1


      
  substr      
   
 lastS    lastS        |