| Step | Hyp | Ref
| Expression |
| 1 | | n0 3560 |
. . 3
 
1c

 1c  |
| 2 | | peano2 4404 |
. . . . . . . 8
 Nn 
1c
Nn  |
| 3 | | tfincl 4493 |
. . . . . . . 8
 
1c
Nn Tfin  1c Nn  |
| 4 | 2, 3 | syl 15 |
. . . . . . 7
 Nn Tfin  1c
Nn  |
| 5 | 4 | adantr 451 |
. . . . . 6
  Nn 
1c Tfin 
1c
Nn  |
| 6 | | tfincl 4493 |
. . . . . . . 8
 Nn Tfin Nn  |
| 7 | | peano2 4404 |
. . . . . . . 8
Tfin
Nn Tfin 1c
Nn  |
| 8 | 6, 7 | syl 15 |
. . . . . . 7
 Nn Tfin 1c
Nn  |
| 9 | 8 | adantr 451 |
. . . . . 6
  Nn 
1c Tfin 1c Nn  |
| 10 | | tfinpw1 4495 |
. . . . . . 7
  
1c
Nn 
1c 1 Tfin  1c  |
| 11 | 2, 10 | sylan 457 |
. . . . . 6
  Nn 
1c 1 Tfin  1c  |
| 12 | | elsuc 4414 |
. . . . . . . 8
  1c 

∼        |
| 13 | | tfinpw1 4495 |
. . . . . . . . . . . 12
  Nn  1
Tfin   |
| 14 | 13 | adantrr 697 |
. . . . . . . . . . 11
  Nn  ∼   1 Tfin   |
| 15 | | vex 2863 |
. . . . . . . . . . . . . . 15
 |
| 16 | 15 | elcompl 3226 |
. . . . . . . . . . . . . 14
 ∼   |
| 17 | | snelpw1 4147 |
. . . . . . . . . . . . . 14
   1   |
| 18 | 16, 17 | xchbinxr 302 |
. . . . . . . . . . . . 13
 ∼   1   |
| 19 | 18 | biimpi 186 |
. . . . . . . . . . . 12
 ∼   1   |
| 20 | 19 | ad2antll 709 |
. . . . . . . . . . 11
  Nn  ∼     1   |
| 21 | | snex 4112 |
. . . . . . . . . . . 12
 
 |
| 22 | 21 | elsuci 4415 |
. . . . . . . . . . 11
  1
Tfin  
1   1
     Tfin 1c  |
| 23 | 14, 20, 22 | syl2anc 642 |
. . . . . . . . . 10
  Nn  ∼    1      Tfin 1c  |
| 24 | | pw1eq 4144 |
. . . . . . . . . . . 12
     1 1       |
| 25 | | pw1un 4164 |
. . . . . . . . . . . . 13
1    
 1 1     |
| 26 | 15 | pw1sn 4166 |
. . . . . . . . . . . . . 14
1  
     |
| 27 | 26 | uneq2i 3416 |
. . . . . . . . . . . . 13
 1 1     1
      |
| 28 | 25, 27 | eqtri 2373 |
. . . . . . . . . . . 12
1    
 1       |
| 29 | 24, 28 | syl6eq 2401 |
. . . . . . . . . . 11
     1  1        |
| 30 | 29 | eleq1d 2419 |
. . . . . . . . . 10
      1
Tfin 1c  1     
Tfin 1c   |
| 31 | 23, 30 | syl5ibrcom 213 |
. . . . . . . . 9
  Nn  ∼   
    1
Tfin 1c   |
| 32 | 31 | rexlimdvva 2746 |
. . . . . . . 8
 Nn    ∼ 
    1
Tfin 1c   |
| 33 | 12, 32 | syl5bi 208 |
. . . . . . 7
 Nn  
1c
1 Tfin 1c   |
| 34 | 33 | imp 418 |
. . . . . 6
  Nn 
1c 1 Tfin 1c  |
| 35 | | nnceleq 4431 |
. . . . . 6
  Tfin  1c Nn Tfin 1c Nn  1
Tfin 
1c
1 Tfin 1c  Tfin 
1c
Tfin 1c  |
| 36 | 5, 9, 11, 34, 35 | syl22anc 1183 |
. . . . 5
  Nn 
1c Tfin 
1c
Tfin 1c  |
| 37 | 36 | ex 423 |
. . . 4
 Nn  
1c
Tfin 
1c
Tfin 1c   |
| 38 | 37 | exlimdv 1636 |
. . 3
 Nn    1c Tfin  1c
Tfin 1c   |
| 39 | 1, 38 | syl5bi 208 |
. 2
 Nn   1c Tfin 
1c
Tfin 1c   |
| 40 | 39 | imp 418 |
1
  Nn  1c  Tfin 
1c
Tfin 1c  |