3 papers
math.SP2026
A Sharp Forbidden Interval for the Nontrivial Adjacency Eigenvalues of Trivially Perfect Graphs
Cristian M. Conde, Ezequiel Dratman, Luciano N. Grippo
We prove a sharp forbidden interval for the nontrivial adjacency eigenvalues of trivially perfect graphs. More precisely, we show that if is a trivially perfect graph, then $\o…
math.CO2024
Singularly cospectral circulant graphs
Cristian M. Conde, Ezequiel Dratman, Luciano N. Grippo +1
Two graphs having the same spectrum are said to be cospectral. Two graphs such that the absolute values of their nonzero eigenvalues coincide are singularly cospectral graphs. Cosp…
math.CO2024
On the spectral radius of unbalanced signed bipartite graphs
Cristian M. Conde, Ezequiel Dratman, Luciano N. Grippo
A signed graph is one that features two types of edges: positive and negative. Balanced signed graphs are those in which all cycles contain an even number of positive edges. In the…