4 citations · 4 across the 4 of their papers we have counts for
10 papers
Computing sandpile configurations using integer linear programming
Carlos A. Alfaro, Carlos E. Valencia, Marcos C. Vargas
It is well known that recurrent sandpile configurations can be characterized as the optimal solution of certain optimization problems. In this article, we present two new integer l…
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…
The structure of sandpile groups of outerplanar graphs
Carlos A. Alfaro, Ralihe R. Villagrán
We compute the sandpile groups of families of planar graphs having a common weak dual by evaluating the indeterminates of the critical ideals of the weak dual at the lengths of the…
Graphs with few trivial characteristic ideals
Carlos A. Alfaro, Michael D. Barrus, John Sinkovic +1
We give a characterization of the graphs with at most three trivial characteristic ideals. This implies the complete characterization of the regular graphs whose critical groups ha…
Eigenvalues, Smith normal form and determinantal ideals
Aida Abiad, Carlos A. Alfaro, Kristin Heysse +1
Determinantal ideals of graphs generalize, among others, the spectrum and the Smith normal form (SNF) of integer matrices associated to graphs. In this work we investigate the rela…
On transversal and 2-packing numbers in uniform linear systems
Carlos A. Alfaro, G. Araujo-Pardo, C. Rubio-Montiel +1
A linear system is a pair where is a family of subsets on a ground finite set , such that , for every $l,l^\prime \in \ma…