Sida Li

collaborators

2 papers

math.CO2025

Strengthened upper bound on the third eigenvalue of graphs

Sida Li

Let $G$ be a graph on $n \geq 3$ vertices, whose adjacency matrix has eigenvalues $λ_{1} \geq λ_{2} \geq \dots \geq λ_{n}$ . The problem of bounding $λ_{k}$ in terms of $n$ was first proposed b…

math.CO2025

On graphs with large third eigenvalue

Giacomo Leonida, Sida Li

Given a graph $G$ , let $λ_{3}$ denote the third largest eigenvalue of its adjacency matrix. In this paper, we prove various results towards the conjecture that $λ_3(G) \le \frac{|V(G…