Description: Define the ordinal number 1. Definition 2.1 of Schloeder p. 4. (Contributed by NM, 29-Oct-1995)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-1o | |- 1o = suc (/) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | c1o | |- 1o |
|
| 1 | c0 | |- (/) |
|
| 2 | 1 | csuc | |- suc (/) |
| 3 | 0 2 | wceq | |- 1o = suc (/) |