Abstract
Let G be a connected graph of order n with Laplacian eigenvalues μ1≥ μ2≥⋯≥μn- 1> μn=0. The Kirchhoff index and the Laplacian-energy-like invariant of G are defined as Kf=n∑k=1n-11/ μk and LEL=∑k=1n-1 μk, respectively. We compare Kf and LEL and establish two sufficient conditions under which LEL<Kf. The connected graphs of order n with nine greatest Kirchhoff indices are determined; for these LEL>Kf holds.
| Original language | English |
|---|---|
| Pages (from-to) | 3661-3671 |
| Number of pages | 11 |
| Journal | Linear Algebra and Its Applications |
| Volume | 436 |
| Issue number | 9 |
| DOIs | |
| State | Published - 1 May 2012 |
Keywords
- Graph spectrum
- Kirchhoff index
- Laplacian spectrum (of graph)
- Laplacian-energy-like invariant
- LEL