A Sharp Upper Bound for the Number of Spanning Trees of a Graph
نویسنده
چکیده
is the diagonal matrix of vertex degrees of G and A(G) is the adjacency matrix ofG. The eigenvalues of L(G) are called the Laplacian eigenvalues and denoted by λ1 ≥ λ2 ≥ · · · ≥ λn = 0. It is well known that λ1 ≤ n. We denote the number of spanning trees (also known as complexity) of G by κ(G). The following formula in terms of the Laplacian eigenvalues of G is well known (see, for example, [2], p. 39):
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عنوان ژورنال:
- Graphs and Combinatorics
دوره 23 شماره
صفحات -
تاریخ انتشار 2007