1 IntroductionIn this note, we shall only consider graphs without multiple edges or loops. If G isa graph, then the set of vertices of G is denoted by V (G), the set of edges of G byE(G), the cardinality of V (G) by | V (G)| , and the complementary graph of G by G. Thesubgraph of G induced by S ⊆ V (G) is denoted by G. A cycle of order n is denotedby Cn. Given a positive integer n, Zn = { 0, 1, 2,


, n − 1} , and S ⊆ { 1, 2,


, ⌊n/2⌋} ,let G be a graph with the vertex set V (G) = Zn and the edge set E(G) = { (x, y) :min{ | x − y| , n − | x − y| } ∈ S} , then G is called a cyclic graph of order n, denoted byGn(S). G is an (s,...