Metamath Proof Explorer


Theorem clnbgrssvtx

Description: The closed neighborhood of a vertex K in a graph is a subset of all vertices of the graph. (Contributed by AV, 9-May-2025)

Ref Expression
Hypothesis clnbgrvtxel.v 𝑉 = ( Vtx ‘ 𝐺 )
Assertion clnbgrssvtx ( 𝐺 ClNeighbVtx 𝐾 ) ⊆ 𝑉

Proof

Step Hyp Ref Expression
1 clnbgrvtxel.v 𝑉 = ( Vtx ‘ 𝐺 )
2 1 clnbgrisvtx ( 𝑛 ∈ ( 𝐺 ClNeighbVtx 𝐾 ) → 𝑛𝑉 )
3 2 ssriv ( 𝐺 ClNeighbVtx 𝐾 ) ⊆ 𝑉