منابع مشابه
Moments in graphs
Let G be a connected graph with vertex set V and a weight function ρ that assigns a nonnegative number to each of its vertices. Then, the ρ-moment of G at vertex u is defined to be M G(u) = ∑ v∈V ρ(v) dist(u, v), where dist(·, ·) stands for the distance function. Adding up all these numbers, we obtain the ρ-moment of G: M G = ∑ u∈V M G(u) = 1 2 ∑ u,v∈V dist(u, v)[ρ(u) + ρ(v)]. This parameter ge...
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Let $G = (V, E)$ be a simple graph. Denote by $D(G)$ the diagonal matrix $diag(d_1,cdots,d_n)$, where $d_i$ is the degree of vertex $i$ and $A(G)$ the adjacency matrix of $G$. The signless Laplacianmatrix of $G$ is $Q(G) = D(G) + A(G)$ and the $k-$th signless Laplacian spectral moment of graph $G$ is defined as $T_k(G)=sum_{i=1}^{n}q_i^{k}$, $kgeqslant 0$, where $q_1$,$q_2$, $cdots$, $q_n$ ...
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let $g$ be a simple graph, and $g^{sigma}$ be an oriented graph of $g$ with the orientation $sigma$ and skew-adjacency matrix $s(g^{sigma})$. the $k-$th skew spectral moment of $g^{sigma}$, denoted by $t_k(g^{sigma})$, is defined as $sum_{i=1}^{n}( lambda_{i})^{k}$, where $lambda_{1}, lambda_{2},cdots, lambda_{n}$ are the eigenvalues of $g^{sigma}$. suppose $g^{sigma...
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let $g = (v, e)$ be a simple graph. denote by $d(g)$ the diagonal matrix $diag(d_1,cdots,d_n)$, where $d_i$ is the degree of vertex $i$ and $a(g)$ the adjacency matrix of $g$. the signless laplacianmatrix of $g$ is $q(g) = d(g) + a(g)$ and the $k-$th signless laplacian spectral moment of graph $g$ is defined as $t_k(g)=sum_{i=1}^{n}q_i^{k}$, $kgeqslant 0$, where $q_1$,$q_2$, $cdots$, $q_n$ ...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 2013
ISSN: 0166-218X
DOI: 10.1016/j.dam.2012.10.024