第二大特征值在(1,2^(1/2))的单圈图的刻画

On Unicyclic Graphs Whose Second Largest Eigenvalue is in(1,2^(1/2))

边数和顶点数相等的连通图称为单圈图,确定了第二大特征值在(1,2^(1/2))的所有单圈图.

Connected graphs in which the number of edges equals the number of vertices are called unicyclic graphs. In this paper, all unicyclic graphs whose second largest eigenvalueis in （1,/2） have been determined.