Description: There is always a set not in y . (Contributed by Scott Fenton, 13-Dec-2010)
Ref | Expression | ||
---|---|---|---|
Assertion | exnel | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elirrv | |
|
2 | 1 | nfth | |
3 | ax8 | |
|
4 | 3 | con3d | |
5 | 2 4 | spime | |
6 | 1 5 | ax-mp | |