Metamath Proof Explorer


Definition df-syms

Description: Define the class of all symmetric sets. It is used only by df-symrels .

Note the similarity of the definitions df-refs , df-syms and df-trs , cf. the comment of dfrefrels2 . (Contributed by Peter Mazsa, 19-Jul-2019)

Ref Expression
Assertion df-syms Syms = x | x dom x × ran x -1 S x dom x × ran x

Detailed syntax breakdown

Step Hyp Ref Expression
0 csyms class Syms
1 vx setvar x
2 1 cv setvar x
3 2 cdm class dom x
4 2 crn class ran x
5 3 4 cxp class dom x × ran x
6 2 5 cin class x dom x × ran x
7 6 ccnv class x dom x × ran x -1
8 cssr class S
9 7 6 8 wbr wff x dom x × ran x -1 S x dom x × ran x
10 9 1 cab class x | x dom x × ran x -1 S x dom x × ran x
11 0 10 wceq wff Syms = x | x dom x × ran x -1 S x dom x × ran x