On the spectral radius of quasi-tree graphs
نویسندگان
چکیده
A connected graphG = (V ,E) is called a quasi-tree, if there exists u0 ∈ V (G) such thatG− u0 is a tree. Denote Q(n, d0) = {G : G is a quasi tree graph of order n with G− u0 being a tree and dG(u0) = d0}. In this paper, we determined the maximal and the second maximal spectral radii of all quasi-tree graphs in the set Q(n, d0). © 2008 Elsevier Inc. All rights reserved. AMS classification: 05C50; 15A18
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