2017/08/26 by Xueyi Huang, Qiongxiang Huang, Huang, Xueyi +3
Mathematics · #05C50 #Combinatorics (math.CO) #FOS: Mathematics #math.CO #msc:05C50
paper · pdf · doi:10.48550/arxiv.1708.07979
17 pages, 3 figures
arxiv created 2017/08/26 · arxiv updated 2017/08/29
Let G be a connected graph on n vertices, and let D(G) be the distance matrix of G. Let ∂1(G)≥∂2(G)≥⋯≥∂n(G) denote the eigenvalues of D(G). In this paper, we characterize all connected graphs with ∂3(G)≤ -1 and ∂n-1(G)≥ -2. By the way, we determine all connected graphs with at most three distance eigenvalues different from -1 and -2.