Description: Define the set of sigma-algebra on a given set. (Contributed by Glauco Siliprandi, 17-Aug-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-salon | |- SalOn = ( x e. _V |-> { s e. SAlg | U. s = x } ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | csalon | |- SalOn |
|
| 1 | vx | |- x |
|
| 2 | cvv | |- _V |
|
| 3 | vs | |- s |
|
| 4 | csalg | |- SAlg |
|
| 5 | 3 | cv | |- s |
| 6 | 5 | cuni | |- U. s |
| 7 | 1 | cv | |- x |
| 8 | 6 7 | wceq | |- U. s = x |
| 9 | 8 3 4 | crab | |- { s e. SAlg | U. s = x } |
| 10 | 1 2 9 | cmpt | |- ( x e. _V |-> { s e. SAlg | U. s = x } ) |
| 11 | 0 10 | wceq | |- SalOn = ( x e. _V |-> { s e. SAlg | U. s = x } ) |