Description: The domain of the repeated composition of a relation is a relation. (Contributed by AV, 12-Jul-2024)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | reldmrelexp | |- Rel dom ^r | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | df-relexp | |- ^r = ( r e. _V , n e. NN0 |-> if ( n = 0 , ( _I |` ( dom r u. ran r ) ) , ( seq 1 ( ( x e. _V , y e. _V |-> ( x o. r ) ) , ( z e. _V |-> r ) ) ` n ) ) ) | |
| 2 | 1 | reldmmpo | |- Rel dom ^r |