Description: Define the class of all singletons. See elsingles for membership. (Contributed by Scott Fenton, 19-Feb-2013)
Ref | Expression | ||
---|---|---|---|
Assertion | df-singles | |
Step | Hyp | Ref | Expression |
---|---|---|---|
0 | csingles | |
|
1 | csingle | |
|
2 | 1 | crn | |
3 | 0 2 | wceq | |