Description: The set of edges of a pseudograph is a subset of the set of unordered pairs of vertices. (Contributed by AV, 24-Nov-2021)
Ref | Expression | ||
---|---|---|---|
Assertion | upgredgssspr | |- ( G e. UPGraph -> ( Edg ` G ) C_ ( Pairs ` ( Vtx ` G ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | upgredgss | |- ( G e. UPGraph -> ( Edg ` G ) C_ { p e. ( ~P ( Vtx ` G ) \ { (/) } ) | ( # ` p ) <_ 2 } ) |
|
2 | fvex | |- ( Vtx ` G ) e. _V |
|
3 | sprvalpwle2 | |- ( ( Vtx ` G ) e. _V -> ( Pairs ` ( Vtx ` G ) ) = { p e. ( ~P ( Vtx ` G ) \ { (/) } ) | ( # ` p ) <_ 2 } ) |
|
4 | 2 3 | ax-mp | |- ( Pairs ` ( Vtx ` G ) ) = { p e. ( ~P ( Vtx ` G ) \ { (/) } ) | ( # ` p ) <_ 2 } |
5 | 1 4 | sseqtrrdi | |- ( G e. UPGraph -> ( Edg ` G ) C_ ( Pairs ` ( Vtx ` G ) ) ) |