Metamath Proof Explorer


Theorem uhgredgiedgb

Description: In a hypergraph, a set is an edge iff it is an indexed edge. (Contributed by AV, 17-Oct-2020)

Ref Expression
Hypothesis uhgredgiedgb.i
|- I = ( iEdg ` G )
Assertion uhgredgiedgb
|- ( G e. UHGraph -> ( E e. ( Edg ` G ) <-> E. x e. dom I E = ( I ` x ) ) )

Proof

Step Hyp Ref Expression
1 uhgredgiedgb.i
 |-  I = ( iEdg ` G )
2 1 uhgrfun
 |-  ( G e. UHGraph -> Fun I )
3 1 edgiedgb
 |-  ( Fun I -> ( E e. ( Edg ` G ) <-> E. x e. dom I E = ( I ` x ) ) )
4 2 3 syl
 |-  ( G e. UHGraph -> ( E e. ( Edg ` G ) <-> E. x e. dom I E = ( I ` x ) ) )