Convex Sets Under Some Graph Operations

Abstract.

 Given a connected graph G, we say that a set C⊆V(G) is convex in G if, for every pair of vertices x,y∈C, the vertex set of every x-y geodesic in G is contained in C. The cardinality of a maximal proper convex set in G is the convexity number of G. In this paper, we characterize the convex sets of graphs resulting from some binary operations, and compute the convexity numbers of the resulting graphs.