Description: A function on a finite set is finitely supported. (Contributed by Mario Carneiro, 20-Jun-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | fisuppfi.1 | |- ( ph -> A e. Fin ) | |
| fisuppfi.2 | |- ( ph -> F : A --> B ) | ||
| Assertion | fisuppfi | |- ( ph -> ( `' F " C ) e. Fin ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | fisuppfi.1 | |- ( ph -> A e. Fin ) | |
| 2 | fisuppfi.2 | |- ( ph -> F : A --> B ) | |
| 3 | cnvimass | |- ( `' F " C ) C_ dom F | |
| 4 | 3 2 | fssdm | |- ( ph -> ( `' F " C ) C_ A ) | 
| 5 | 1 4 | ssfid | |- ( ph -> ( `' F " C ) e. Fin ) |