Extremal graphs for the sum of the two largest signless Laplacian eigenvalues
نویسندگان
چکیده
منابع مشابه
Some remarks on the sum of the inverse values of the normalized signless Laplacian eigenvalues of graphs
Let G=(V,E), $V={v_1,v_2,ldots,v_n}$, be a simple connected graph with $%n$ vertices, $m$ edges and a sequence of vertex degrees $d_1geqd_2geqcdotsgeq d_n>0$, $d_i=d(v_i)$. Let ${A}=(a_{ij})_{ntimes n}$ and ${%D}=mathrm{diag }(d_1,d_2,ldots , d_n)$ be the adjacency and the diagonaldegree matrix of $G$, respectively. Denote by ${mathcal{L}^+}(G)={D}^{-1/2}(D+A) {D}^{-1/2}$ the normalized signles...
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ژورنال
عنوان ژورنال: The Electronic Journal of Linear Algebra
سال: 2015
ISSN: 1081-3810
DOI: 10.13001/1081-3810.3143