arXiv subjects

Lucas Portugal

Publications and source records attributed to Lucas Portugal.

2 recordsLinked to original sources

arXiv2026

On the spectra of k-uniform threshold hypergraphs

In this article we introduce a definition of k-uniform thresholds hypergraphs through a binary sequence, a natural extension of the classical definition for thresholds graphs. We characterize some of its eigenvalues and multiplicities by means of combinatorial numbers, derived from edge counts. An important problem addressed in Spectral Graph Theory is to find graphs with few distinct eigenvalues. Our characterization allows us to construct k-uniform threshold hypergraphs having an arbitrary number of vertices with few distinct eigenvalues.

math.CO↗

arXiv2021

Adjacency Energy of Hypergraphs

In this paper, we define and obtain several properties of the (adjacency) energy of a hypergraph. In particular, bounds for this energy are obtained as functions of structural and spectral parameters, such as Zagreb index and spectral radius. We also study how the energy of a hypergraph varies when a vertex/edge is removed or when an edge is divied. In addition, we solved the extremal problem energy for the class of hyperstars, and show that the energy of a hypergraph is never an odd number.

math.CO↗