Theorem ttctr3

Description: The transitive closure of a class is transitive. (Contributed by Matthew House, 6-Apr-2026)

	Ref	Expression
Assertion	ttctr3	Could not format assertion : No typesetting found for |- U. TC+ A C_ TC+ A with typecode |-

Proof

Step	Hyp	Ref	Expression
1		ttctr	Could not format Tr TC+ A : No typesetting found for |- Tr TC+ A with typecode |-
2		df-tr	Could not format ( Tr TC+ A <-> U. TC+ A C_ TC+ A ) : No typesetting found for |- ( Tr TC+ A <-> U. TC+ A C_ TC+ A ) with typecode |-
3	1 2	mpbi	Could not format U. TC+ A C_ TC+ A : No typesetting found for |- U. TC+ A C_ TC+ A with typecode |-