Injective Chromatic Sum and Injective Chromatic Polynomials of Graphs
نویسندگان
چکیده
The injective chromatic number χi(G) [5] of a graph G is the minimum number of colors needed to color the vertices of G such that two vertices with a common neighbor are assigned distinct colors. In this paper we define injective chromatic sum and injective strength of a graph and obtain the injective chromatic sum of complete graph, paths, cycles, wheel graph and complete bipartite graph. We also suggest bounds for injective chromatic sum. The injective chromatic sum of graph complements, join, union, product and corona is discussed.The concept of injective chromatic polynomial is introduced and computed for complete graphs, bipartite graphs, cycles etc. The bounds for the injective chromatic polynomial of trees is suggested.
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