Description: A permutation (element of the symmetric group) is a function from a set into itself. (Contributed by AV, 1-Jan-2019)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | symgbas.1 | |- G = ( SymGrp ` A ) |
|
| symgbas.2 | |- B = ( Base ` G ) |
||
| Assertion | symgbasf | |- ( F e. B -> F : A --> A ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | symgbas.1 | |- G = ( SymGrp ` A ) |
|
| 2 | symgbas.2 | |- B = ( Base ` G ) |
|
| 3 | 1 2 | symgbasf1o | |- ( F e. B -> F : A -1-1-onto-> A ) |
| 4 | f1of | |- ( F : A -1-1-onto-> A -> F : A --> A ) |
|
| 5 | 3 4 | syl | |- ( F e. B -> F : A --> A ) |