A note on some lower bounds of the Laplacian energy of a graph

Document Type : Research Paper


1 Faculty of Electronic Engineering

2 University of Nis, Serbia

3 University of Management and Technology, Sialkot, Pakistan


‎‎‎For a simple connected graph $G$ of order $n$ and size $m$‎, ‎the Laplacian energy of $G$ is defined as‎ ‎$LE(G)=\sum_{i=1}^n|\mu_i-\frac{2m}{n}|$ where $\mu_1‎, ‎\mu_2,\ldots‎,‎‎\mu_{n-1}‎, ‎\mu_{n}$‎ ‎are the Laplacian eigenvalues of $G$ satisfying $\mu_1\ge \mu_2\ge\cdots \ge \mu_{n-1}>‎ ‎\mu_{n}=0$‎. ‎In this note‎, ‎some new lower bounds on the graph invariant $LE(G)$ are derived‎. ‎The obtained results are compared with some already known lower bounds of $LE(G)$‎.


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