2 papers
math.CO2020
Enumeration of cospectral and coinvariant graphs
Aida Abiad, Carlos A. Alfaro
We present enumeration results on the number of connected graphs up to 10 vertices for which there is at least one other graph with the same spectrum (a cospectral mate), or at lea…
math.CO2017
Digraphs with at most one trivial critical ideal
Carlos A. Alfaro, Carlos E. Valencia, Adrián Vázquez-Ávila
Critical ideals generalize the critical group, Smith group and the characteristic polynomials of the adjacency and Laplacian matrices of a graph. We give a complete characterizatio…