The Least Eigenvalue of Unicyclic Graphs with Application to Spectral Spread  

作　　者：Jiming Guo Gege Zhang Zhiwen Wang Panpan Tong 

机构地区：[1]School of Mathematics,East China University of Science and Technology Shanghai 200237,China

出　　处：《Algebra Colloquium》2022年第2期265-272,共8页代数集刊（英文版）

基　　金：supported by NSFC(No.12171154).

摘　　要：Let U^(g)_(n)be the set of connected unicyclic graphs of order n and girth g.Let C(T_(1),T_(2),…,T_(g))∈U^(g)_(n)be obtained from a cycle v_(1)v_(2)…v_(g)v_(1)(in an anticlockwise direction)by identifying v_(i)with the root of a rooted tree T_(i)of order n_(i)for each i=1,2,…,g,where n_(i)≥1 and∑^(g)_(i=1)n_(i)=n.In this note,the graph with the minimal least eigenvalue(and the graph with maximal spread)in C(T_(1),T_(2),…,T_(g))is determined.

关 键 词：adjacency matrix least eigenvalue EIGENVECTOR unicyclic graph 

分 类 号：O15[理学—数学]