For every two vertices u and u, I[u, υ] denotes the closed interval consisting of u, υ and all vertices lying on some u ― υ geodesic. A Subset S of V(G) is called a geodesic set if I[S] = V(G), where I[S] = ∪_((u,υ)∈S)I[u, υ]. The geodesic number of a connected graph G is defined as the cardinality of a minimum geodesic set. The convex hull of a subset S of V(G), where G is a connected graph, is defined as the smallest convex set in G containing S. The hull number of G is the cardinality of smallest set S whose convex hull is V(G). In this paper, we give the geodesic number and the hull number of the sum of two connected graphs.
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