Description: All variables are effectively bound in a distinct variable specifier. Version of nfnae with a disjoint variable condition, which does not require ax-13 . (Contributed by Mario Carneiro, 11-Aug-2016) (Revised by Gino Giotto, 10-Jan-2024)
Ref | Expression | ||
---|---|---|---|
Assertion | nfnaew | |- F/ z -. A. x x = y |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | hbaev | |- ( A. x x = y -> A. z A. x x = y ) |
|
2 | 1 | nf5i | |- F/ z A. x x = y |
3 | 2 | nfn | |- F/ z -. A. x x = y |