Metamath Proof Explorer


Definition df-trcl

Description: Transitive closure of a relation. This is the smallest superset which has the transitive property. (Contributed by FL, 27-Jun-2011)

Ref Expression
Assertion df-trcl
|- t+ = ( x e. _V |-> |^| { z | ( x C_ z /\ ( z o. z ) C_ z ) } )

Detailed syntax breakdown

Step Hyp Ref Expression
0 ctcl
 |-  t+
1 vx
 |-  x
2 cvv
 |-  _V
3 vz
 |-  z
4 1 cv
 |-  x
5 3 cv
 |-  z
6 4 5 wss
 |-  x C_ z
7 5 5 ccom
 |-  ( z o. z )
8 7 5 wss
 |-  ( z o. z ) C_ z
9 6 8 wa
 |-  ( x C_ z /\ ( z o. z ) C_ z )
10 9 3 cab
 |-  { z | ( x C_ z /\ ( z o. z ) C_ z ) }
11 10 cint
 |-  |^| { z | ( x C_ z /\ ( z o. z ) C_ z ) }
12 1 2 11 cmpt
 |-  ( x e. _V |-> |^| { z | ( x C_ z /\ ( z o. z ) C_ z ) } )
13 0 12 wceq
 |-  t+ = ( x e. _V |-> |^| { z | ( x C_ z /\ ( z o. z ) C_ z ) } )