Title of article :
The Signless Laplacian Estrada Index of Unicyclic Graphs
Author/Authors :
Ellahi ، Hamid Reza - University of Qom , Nasiri ، Ramin - University of Qom , Fath-Tabar ، Gholam Hossein - University of Kahsan , Gholami ، Ahmad - University of Qom
Abstract :
For a simple graph G , the signless Laplacian Estrada index is defined as SLEE(G)=Σ^ n _i=1 e^ q^i, where q1; q2; : : : ; qn are the eigenvalues of the signless Laplacian matrix of G . In this paper, we first characterize the unicyclic graphs with the first two largest and smallest $SLEE$’s and then determine the unique unicyclic graph with maximum $SLEE$ among all unicyclic graphs on n vertices with a given diameter. All extremal graphs, which have been introduced in our results are also extremal with respect to the signless Laplacian resolvent energy.
Keywords :
Signless Laplacian Estrada index , unicyclic graphs , extremal graphs , diameter , signless Laplacian resolvent energy.
Journal title :
Mathematics Interdisciplinary Research
Journal title :
Mathematics Interdisciplinary Research