ON -CORDIAL LABELLING OF M-GRAPHS
Let be a graph on p vertices with where is the minimum degree among the vertices of G. A graph G is -cordial, if it is possible to label the edges of G with the numbers from the set in such a way that at each vertex v, the sum modulo k of the labels on the edges incident with v satisfies the inequalities and for all i, j, where and are, respectively, the number of vertices labelled with i and the number of edges labelled with j. In this paper, we define a new graph obtained by joining the central vertex of a wheel to the end vertex of a path by an edge e. We call this graph M-graph and is denoted by We prove that for some values of m and n, the M-graph is -cordial provided that k is odd. We also prove that when the M-graph is -cordial for all and is -cordial.
-cordial labelling, M-graph.