Transactions on Combinatorics (Jun 2019)
A note on some lower bounds of the Laplacian energy of a graph
Abstract
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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