On the skew spectral moments of graphs

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...

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Bibliographic Details
Main Authors: Fatemeh Taghvaee, Gholam Hossein Fath-Tabar
Format: Article
Language:English
Published: University of Isfahan 2017-03-01
Series:Transactions on Combinatorics
Subjects:
Online Access:http://toc.ui.ac.ir/article_20737_9c81a151b424aac06fc6253943dc89a2.pdf
Description
Summary: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 ‎$G^{sigma_1}_{1}$ and $G^{sigma_2}_{2}$ are two digraphs‎. ‎If there‎ ‎exists an integer $k$‎, ‎$1 leq k leq n-1$‎, ‎such that for each‎ ‎$i$‎, ‎$0 leq i leq k-1$‎, ‎$T_i(G^{sigma_1}_{1}) =‎ ‎T_i(G^{sigma_2}_{2})$ and‎ ‎$T_k(G^{sigma_1}_{1})
ISSN:2251-8657
2251-8665