13 citations · 21 across the 7 of their papers we have counts for
7 papers
Limit points of (signless) Laplacian spectral radii of linear trees
Francesco Belardo, Elismar R. Oliveira, Vilmar Trevisan
We study limit points of the spectral radii of Laplacian matrices of graphs. We adapted the method used by J. B. Shearer in 1989, devised to prove the density of adjacency limit po…
On the divisibility of H-shape trees and their spectral determination
Zhen Chen, Jianfeng Wang, Maurizio Brunetti +1
A graph is divisible by a graph if the characteristic polynomial of is divisible by that of . In this paper, a necessary and sufficient condition for recursive graph…
A switching method for constructing cospectral gain graphs
Aida Abiad, Francesco Belardo, Antonina P. Khramova
A gain graph over a group , also referred to as -gain graph, is a graph where an element of a group , called gain, is assigned to each oriented edge, in such a way that th…
The -apex trees with minimum augmented Zagreb index
Muhuo Liu, Shumei Pang, Francesco Belardo +1
For a connected graph on at least three vertices, the augmented Zagreb index (AZI) of is defined as $$AZI(G)=\sum_{uv\in E(G)}\left(\frac{d(u)d(v)}{d(u)+d(v)-2}\right)^{3},…
Constructing cospectral signed graphs
Francesco Belardo, Maurizio Brunetti, Matteo Cavaleri +1
A well--known fact in Spectral Graph Theory is the existence of pairs of isospectral nonisomorphic graphs (known as PINGS). The work of A.J. Schwenk (in 1973) and of C. Godsil and…
Total graph of a signed graph
Francesco Belardo, Zoran Stanić, Thomas Zaslavsky
The total graph is built by joining the graph to its line graph by means of the incidences. We introduce a similar construction for signed graphs. Under two similar definitions of…
Open problems in the spectral theory of signed graphs
Francesco Belardo, Sebastian M. Cioabă, Jack H. Koolen +1
Signed graphs are graphs whose edges get a sign or (the signature). Signed graphs can be studied by means of graph matrices extended to signed graphs in a natural way. Re…