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 ∈ V ↦ ∩ { 𝑧 ∣ ( 𝑥 ⊆ 𝑧 ∧ ( 𝑧 ∘ 𝑧 ) ⊆ 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 ⊆ 𝑧
7 5 5 ccom ⊢ ( 𝑧 ∘ 𝑧 )
8 7 5 wss ⊢ ( 𝑧 ∘ 𝑧 ) ⊆ 𝑧
9 6 8 wa ⊢ ( 𝑥 ⊆ 𝑧 ∧ ( 𝑧 ∘ 𝑧 ) ⊆ 𝑧 )
10 9 3 cab ⊢ { 𝑧 ∣ ( 𝑥 ⊆ 𝑧 ∧ ( 𝑧 ∘ 𝑧 ) ⊆ 𝑧 ) }
11 10 cint ⊢ ∩ { 𝑧 ∣ ( 𝑥 ⊆ 𝑧 ∧ ( 𝑧 ∘ 𝑧 ) ⊆ 𝑧 ) }
12 1 2 11 cmpt ⊢ ( 𝑥 ∈ V ↦ ∩ { 𝑧 ∣ ( 𝑥 ⊆ 𝑧 ∧ ( 𝑧 ∘ 𝑧 ) ⊆ 𝑧 ) } )
13 0 12 wceq ⊢ t+ = ( 𝑥 ∈ V ↦ ∩ { 𝑧 ∣ ( 𝑥 ⊆ 𝑧 ∧ ( 𝑧 ∘ 𝑧 ) ⊆ 𝑧 ) } )