Ela on the Spectral Moment of Graphs with K Cut Edges
نویسندگان
چکیده
Let A(G) be the adjacency matrix of a graph G with λ1(G), λ2(G), . . . , λn(G) its eigenvalues in non-increasing order. Call the number Sk(G) := ∑ n i=1 λ i (G) (k = 0, 1, . . . , n − 1) the kth spectral moment of G. Let S(G) = (S0(G), S1(G), . . . , Sn−1(G)) be the sequence of spectral moments of G. For two graphsG1 and G2, we have G1 ≺s G2 if Si(G1) = Si(G2) for i = 0, 1, . . . , k−1 and Sk(G1) < Sk(G2) for some k ∈ {1, 2, . . . , n − 1}. Denote by G k n the set of connected n-vertex graphs with k cut edges. In this paper, the first, the second, the last and the penultimate graphs, in the S-order, are determined among G k n , respectively.
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