English

Graphs with at most three distance eigenvalues different from $-1$ and $-2$

Combinatorics 2017-08-29 v1

Abstract

Let GG be a connected graph on nn vertices, and let D(G)D(G) be the distance matrix of GG. Let 1(G)2(G)n(G)\partial_1(G)\ge\partial_2(G)\ge\cdots\ge\partial_n(G) denote the eigenvalues of D(G)D(G). In this paper, we characterize all connected graphs with 3(G)1\partial_{3}(G)\leq -1 and n1(G)2\partial_{n-1}(G)\geq -2. By the way, we determine all connected graphs with at most three distance eigenvalues different from 1-1 and 2-2.

Keywords

Cite

@article{arxiv.1708.07979,
  title  = {Graphs with at most three distance eigenvalues different from $-1$ and $-2$},
  author = {Xueyi Huang and Qiongxiang Huang and Lu Lu},
  journal= {arXiv preprint arXiv:1708.07979},
  year   = {2017}
}

Comments

17 pages, 3 figures

R2 v1 2026-06-22T21:24:16.435Z