Proof of Theorem riscer
| Step | Hyp | Ref
| Expression |
| 1 | | visset 2295 |
. . . 4
 |
| 2 | | visset 2295 |
. . . 4
 |
| 3 | 1, 2 | isrisc 16139 |
. . 3
      Ring Ring   RngIso     |
| 4 | | rngisocnv 16135 |
. . . . . . 7
  Ring
Ring  RngIso     RngIso    |
| 5 | 4 | 3expia 1069 |
. . . . . 6
  Ring
Ring   RngIso    RngIso     |
| 6 | | risci 16141 |
. . . . . . . 8
  Ring
Ring   RngIso        |
| 7 | 6 | 3expia 1069 |
. . . . . . 7
  Ring
Ring    RngIso        |
| 8 | 7 | ancoms 484 |
. . . . . 6
  Ring
Ring    RngIso        |
| 9 | 5, 8 | syld 30 |
. . . . 5
  Ring
Ring   RngIso        |
| 10 | 9 | 19.23adv 1584 |
. . . 4
  Ring
Ring    RngIso        |
| 11 | 10 | imp 377 |
. . 3
   Ring Ring   RngIso        |
| 12 | 3, 11 | sylbi 216 |
. 2
         |
| 13 | | rngisoco 16136 |
. . . . . . . . . . 11
   Ring Ring
Ring   RngIso   RngIso       RngIso    |
| 14 | 13 | ex 402 |
. . . . . . . . . 10
  Ring
Ring Ring    RngIso   RngIso      RngIso     |
| 15 | | risci 16141 |
. . . . . . . . . . . 12
  Ring
Ring    RngIso        |
| 16 | 15 | 3expia 1069 |
. . . . . . . . . . 11
  Ring
Ring     RngIso        |
| 17 | 16 | 3adant2 895 |
. . . . . . . . . 10
  Ring
Ring Ring     RngIso        |
| 18 | 14, 17 | syld 30 |
. . . . . . . . 9
  Ring
Ring Ring    RngIso   RngIso         |
| 19 | 18 | 19.23advv 1676 |
. . . . . . . 8
  Ring
Ring Ring        RngIso   RngIso         |
| 20 | | eeanv 1707 |
. . . . . . . 8
       RngIso   RngIso      RngIso    RngIso     |
| 21 | 19, 20 | syl5ibr 224 |
. . . . . . 7
  Ring
Ring Ring     RngIso    RngIso         |
| 22 | 21 | 3expb 1068 |
. . . . . 6
  Ring  Ring
Ring     RngIso    RngIso         |
| 23 | 22 | adantlr 429 |
. . . . 5
   Ring Ring  Ring Ring     RngIso    RngIso         |
| 24 | 23 | imp 377 |
. . . 4
    Ring
Ring
 Ring
Ring    RngIso    RngIso         |
| 25 | 24 | an4s 566 |
. . 3
    Ring
Ring

 RngIso     Ring Ring   RngIso         |
| 26 | | visset 2295 |
. . . 4
 |
| 27 | 2, 26 | isrisc 16139 |
. . 3
      Ring Ring   RngIso     |
| 28 | 25, 3, 27 | syl2anb 504 |
. 2
              |
| 29 | 12, 28 | ster 5325 |
1
  |