{ "id": "1209.2188", "version": "v1", "published": "2012-09-11T00:50:05.000Z", "updated": "2012-09-11T00:50:05.000Z", "title": "On the spectral moment of trees with given degree sequences", "authors": [ "Li Shuchao", "Song Yibing" ], "comment": "9 pages; 1 figure", "categories": [ "math.CO" ], "abstract": "Let $A(G)$ be the adjacency matrix of graph $G$ with eigenvalues $\\lambda_1(G), \\lambda_2(G),..., \\lambda_n(G)$ in non-increasing order. The number $S_k(G):=\\sum_{i=1}^{n}\\lambda_i^{k}(G)\\, (k=0, 1,..., n-1)$ is called the $k$th spectral moment of $G$. Let $S(G) = (S_0(G), S_1(G),..., S_{n-1}(G))$ be the sequence of spectral moments of $G.$ For two graphs $G_1, G_2$, we have $G_1\\prec_{s}G_2$ if for some $k \\in \\{1,2,3,...,n-1\\}$, we have $S_i(G_1) = S_i(G_2)\\, ,\\, i = 0, 1,..., k-1$ and $S_k(G_1)