theorem nfrapp {x: nat} (F: set x) (a: nat x): $ FS/ x F $ > $ FN/ x a $ > $ FS/ x F @' a $;
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | hyp h2 | FN/ x a |
|
2 | nfnv | FN/ x a1 |
|
3 | 1, 2 | nfpr | FN/ x a, a1 |
4 | hyp h1 | FS/ x F |
|
5 | 3, 4 | nfel | F/ x a, a1 e. F |
6 | 5 | nfab | FS/ x {a1 | a, a1 e. F} |
7 | 6 | conv rapp | FS/ x F @' a |