Journal of Applied Mathematics
Volume 2013 (2013), Article ID 681019, 6 pages
http://dx.doi.org/10.1155/2013/681019
Research Article

Bounds on the Distance Energy and the Distance Estrada Index of Strongly Quotient Graphs

Ş. Burcu Bozkurt,1 Chandrashekara Adiga,2 and Durmuş Bozkurt1

1Department of Mathematics, Science Faculty, Selçuk University, 42075 Konya, Turkey
2Department of Studies in Mathematics, University of Mysore, Manasagangotri, Mysore 570 006, India

Received 31 January 2013; Accepted 19 April 2013

Academic Editor: Chong Lin

Copyright © 2013 Ş. Burcu Bozkurt et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The notion of strongly quotient graph (SQG) was introduced by Adiga et al. (2007). In this paper, we obtain some better results for the distance energy and the distance Estrada index of any connected strongly quotient graph (CSQG) as well as some relations between the distance Estrada index and the distance energy. We also present some bounds for the distance energy and the distance Estrada index of CSQG whose diameter does not exceed two. Additionally, we show that our results improve most of the results obtained by Güngör and Bozkurt (2009) and Zaferani (2008).