The Lower Bounds of the Least Eigenvalue of Complements of Bicyclic Graphs with n-4 Pendant Vertices
The least eigenvalue as a parameter to characterize the structural properties of a graph,has important research value.Comparing with the spectral radius,the least eigenvalue of a graph is less studied.The graphs in this paper are simple,undirected and connected,and we characterize the lower bounds of the least adjacency eigenvalue of graphs in the set of bicyclic graphs with n vertices and n-4 pendant vertices by using relevant knowledge analysis and demonstration.