Independence number in graphs and its upper bounds

Document Type : Research Paper

Author

Department of Mathematics, Faculty of Science, Razi University, Kermanshah, Iran

Abstract

‎In this paper, we use the double counting method to find some upper bounds for the independence number of a simple graph in terms of its order, size and  maximum degree.   Moreover,  we determine extremal graphs attaining equality in upper bounds.  In addition, some lower bounds for the energy of graphs in terms of their size and maximum degree and the number of odd cycle, are determined.

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