Description: Bound-variable hypothesis builder for "all some one" restricted to a class. This is the "all some one" counterpart of nfrals . (Contributed by David A. Wheeler, 21-Jul-2026)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | nfralseu.1 | |- F/_ x A |
|
| nfralseu.2 | |- F/ x ph |
||
| nfralseu.3 | |- F/ x ps |
||
| Assertion | nfralseu | |- F/ x AE! y e. A ( ph -> ps ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | nfralseu.1 | |- F/_ x A |
|
| 2 | nfralseu.2 | |- F/ x ph |
|
| 3 | nfralseu.3 | |- F/ x ps |
|
| 4 | df-ralseu | |- ( AE! y e. A ( ph -> ps ) <-> ( A. y e. A ( ph -> ps ) /\ E! y e. A ph ) ) |
|
| 5 | 2 3 | nfim | |- F/ x ( ph -> ps ) |
| 6 | 1 5 | nfralw | |- F/ x A. y e. A ( ph -> ps ) |
| 7 | 1 2 | nfreuw | |- F/ x E! y e. A ph |
| 8 | 6 7 | nfan | |- F/ x ( A. y e. A ( ph -> ps ) /\ E! y e. A ph ) |
| 9 | 4 8 | nfxfr | |- F/ x AE! y e. A ( ph -> ps ) |