Description: The transitive closure of a class is a relation. (Contributed by Scott Fenton, 17-Oct-2024)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | relttrcl | |- Rel t++ R | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | df-ttrcl |  |-  t++ R = { <. x , y >. | E. n e. ( _om \ 1o ) E. f ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. m e. n ( f ` m ) R ( f ` suc m ) ) } | |
| 2 | 1 | relopabi | |- Rel t++ R |