Description: The neighbors of a vertex K in a graph form a subset of all vertices of the graph. (Contributed by Alexander van der Vekens, 12-Oct-2017) (Revised by AV, 26-Oct-2020) (Revised by AV, 12-Feb-2022)
Ref | Expression | ||
---|---|---|---|
Hypothesis | nbgrisvtx.v | |- V = ( Vtx ` G ) |
|
Assertion | nbgrssvtx | |- ( G NeighbVtx K ) C_ V |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nbgrisvtx.v | |- V = ( Vtx ` G ) |
|
2 | 1 | nbgrisvtx | |- ( n e. ( G NeighbVtx K ) -> n e. V ) |
3 | 2 | ssriv | |- ( G NeighbVtx K ) C_ V |