Description: Equality theorem for supremum of sets of ordinals. (Contributed by RP, 23-Jan-2025)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | rp-intrabeq | |- ( A = B -> |^| { x e. On | A. y e. A y C_ x } = |^| { x e. On | A. y e. B y C_ x } ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | raleq | |- ( A = B -> ( A. y e. A y C_ x <-> A. y e. B y C_ x ) ) |
|
| 2 | 1 | rabbidv | |- ( A = B -> { x e. On | A. y e. A y C_ x } = { x e. On | A. y e. B y C_ x } ) |
| 3 | 2 | inteqd | |- ( A = B -> |^| { x e. On | A. y e. A y C_ x } = |^| { x e. On | A. y e. B y C_ x } ) |