Description: Obsolete version of predon as of 16-Oct-2024. (Contributed by Scott Fenton, 27-Mar-2011) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | predonOLD | |- ( A e. On -> Pred ( _E , On , A ) = A ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | predep | |- ( A e. On -> Pred ( _E , On , A ) = ( On i^i A ) ) |
|
| 2 | onss | |- ( A e. On -> A C_ On ) |
|
| 3 | sseqin2 | |- ( A C_ On <-> ( On i^i A ) = A ) |
|
| 4 | 2 3 | sylib | |- ( A e. On -> ( On i^i A ) = A ) |
| 5 | 1 4 | eqtrd | |- ( A e. On -> Pred ( _E , On , A ) = A ) |