Characteristics polynomial of normalized Laplacian for trees
نویسندگان
چکیده
Here, we find the characteristics polynomial of normalized Laplacian of a tree. The coefficients of this polynomial are expressed by the higher order general Randić indices for matching, whose values depend on the structure of the tree. We also find the expression of these indices for starlike tree and a double-starlike tree, Hm(p, q). Moreover, we show that two cospectral Hm(p, q) of the same diameter are isomorphic. AMS classification: 05C50; 05C05. Keywards: Normalized Laplacian; Characteristics Polynomial; Tree; Starlike tree; Double Starlike tree; Randić index; Matching; General Randić index for matching; Eigenvalue 1.
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ورودعنوان ژورنال:
- Applied Mathematics and Computation
دوره 271 شماره
صفحات -
تاریخ انتشار 2015