一个图G的邻接矩阵A(G)是n\times n矩阵,如果v_i和v_j相邻, 那么它的(i,j)位置为1, 否则为0.
图G的谱半径是邻接矩阵A(G)的最大特征值.
本文确定了在所有的树和所有的二部单圈图、二部双圈图、二部三圈图、二部四圈图、二部五圈
图以及二部拟树图中 所对应的具有最大谱半径的图.
The adjacency matrix A(G) of a graph G is the n\times
n matrix with its (i,j)-entry equal to 1 if v_i and v_j are
adjacent, and 0 otherwise. The spectral radius of G is the
largest eigenvalue of A(G). In this paper we determine the graphs
with maximum spectral radius among all trees, and all bipartite
unicyclic, bicyclic, tricyclic, tetracyclic, pentacyclic and
quasi-tree graphs, respectively.
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