Description: Define the surreal integers. Compare dfz2 . (Contributed by Scott Fenton, 17-May-2025)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-zs | |- ZZ_s = ( -s " ( NN_s X. NN_s ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | czs | |- ZZ_s |
|
| 1 | csubs | |- -s |
|
| 2 | cnns | |- NN_s |
|
| 3 | 2 2 | cxp | |- ( NN_s X. NN_s ) |
| 4 | 1 3 | cima | |- ( -s " ( NN_s X. NN_s ) ) |
| 5 | 0 4 | wceq | |- ZZ_s = ( -s " ( NN_s X. NN_s ) ) |