Metamath Proof Explorer


Definition df-nelbr

Description: Define negated membership as binary relation. Analogous to df-eprel (the membership relation). (Contributed by AV, 26-Dec-2021)

Ref Expression
Assertion df-nelbr =xy|¬xy

Detailed syntax breakdown

Step Hyp Ref Expression
0 cnelbr class
1 vx setvarx
2 vy setvary
3 1 cv setvarx
4 2 cv setvary
5 3 4 wcel wffxy
6 5 wn wff¬xy
7 6 1 2 copab classxy|¬xy
8 0 7 wceq wff=xy|¬xy