Metamath Proof Explorer


Definition df-fin5

Description: A set is V-finite iff it behaves finitely under |_| . Definition V of Levy58 p. 3. (Contributed by Stefan O'Rear, 12-Nov-2014)

Ref Expression
Assertion df-fin5 FinV=x|x=xx⊔︀x

Detailed syntax breakdown

Step Hyp Ref Expression
0 cfin5 classFinV
1 vx setvarx
2 1 cv setvarx
3 c0 class
4 2 3 wceq wffx=
5 csdm class
6 2 2 cdju classx⊔︀x
7 2 6 5 wbr wffxx⊔︀x
8 4 7 wo wffx=xx⊔︀x
9 8 1 cab classx|x=xx⊔︀x
10 0 9 wceq wffFinV=x|x=xx⊔︀x