On the Non-Common Neighbourhood Energy of Graphs

Ahmad N. Al-Kenani¹, Anwar Alwardi², Omar A. Al-Attas¹

¹Department of Mathematics, King Abdulaziz University, Jeddah, Saudi Arabia.
²Department of Studies in Mathematics, University of Mysore, Mysore, India.

DOI: 10.4236/am.2015.68108                

Abstract

In this paper, we introduce a new type of graph energy called the non-common-neighborhood energy , , NCN-energy for some standard graphs is obtained and an upper bound for  is found when G is a strongly regular graph. Also the relation between common neigh-bourhood energy and non-common neighbourhood energy of a graph is established.

Keywords

NCN-Eigenvalues (of Graph), NCN-Energy (of Graph), NCN-Adjacency Matrix (of Graph)

Conflicts of Interest

The authors declare no conflicts of interest.

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