Description: Consequence of the not-free predicate. (Contributed by Mario Carneiro, 11-Aug-2016) Avoid ax-10 , ax-11 . (Revised by Gino Giotto, 23-May-2024)
Ref | Expression | ||
---|---|---|---|
Hypothesis | nfcrii.1 | |- F/_ x A |
|
Assertion | nfcrii | |- ( y e. A -> A. x y e. A ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nfcrii.1 | |- F/_ x A |
|
2 | 1 | nfcri | |- F/ x y e. A |
3 | 2 | nf5ri | |- ( y e. A -> A. x y e. A ) |