2 papers
math.CO2026
Constructions of almost controllable graphs determined by their generalized spectra
Wei Wang, Manjin Shi, Fenjin Liu
Identifying and constructing graphs that are determined by their generalized spectrum (DGS) is a significant and challenging problem in spectral graph theory. Recently, a simple cr…
math.CO2026
Signed graphs with exactly two main eigenvalues: The unicyclic case
Zenan Du, Fenjin Liu, Hechao Liu +2
An eigenvalue of a signed graph of order is called a main eigenvalue if its eigenspace is not orthogonal to the all-ones vector . Characterizing signed graphs with…