摘要
Schuster, Cai Maocheng and Lin Yixun studied the interpolation theory for the number of end vertices of spanning trees of graph. Zhang Fuji and Guo Xiaofeng obtained the related result of digraph. This paper is devoted to find the upper and lower bounds of the maximum number of end vertices of spanning (directed) trees for directed or undirected graphs. Our result is connected with some parameters in graph theory such as cyclomatic number and absorption number. For our purpose,
