RT info:eu-repo/semantics/article T1 Structural and spectral properties of minimal strong digraphs A1 Marijuán López, Carlos A1 García López, Jesús A1 Pozo Coronado, Luis Miguel K1 Digraphs K1 Dígrafos K1 Trees K1 Árboles K1 Characteristic polynomial K1 Polinomio característico AB In this article, we focus on structural and spectral properties of minimal strongdigraphs (MSDs). We carry out a comparative study of properties of MSDs versustrees. This analysis includes two new properties. The first one gives bounds onthe coefficients of characteristic polynomials of trees (double directed trees), andconjectures the generalization of these bounds to MSDs. As a particular case, weprove that the independent coemcient of the characteristic polynomial of a tree oran MSD must be — 1, 0 or 1. For trees, this fact means that a tree has at most oneperfect matching; for MSDs, it means that an MSD has at most one covering bydisjoint cycles. The property states that every MSD can be decomposed in a rootedspanning tree and a forest of reversed rooted trees, as factors. In our opinión, theanalogies described suppose a significative change in the traditional point of viewabout this class of digraphs. PB Elsevier SN 1571-0653 YR 2016 FD 2016 LK http://uvadoc.uva.es/handle/10324/40734 UL http://uvadoc.uva.es/handle/10324/40734 LA eng NO Electronic Notes in Discrete Mathematics, 2016, vol. 54. p. 91-96 NO Producción Científica DS UVaDOC RD 24-nov-2024