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 A216122 The Wiener index of the nanostar dendrimer NS[n], defined pictorially in the Ashrafi et al. reference. 1
 94698, 1317858, 10315218, 63835698, 349594098, 1781094258, 8661794418, 40799683698, 187793424498, 849479276658, 3790907541618, 16734956611698, 73223518070898, 318024922835058, 1372613885896818, 5892491154499698, 25178059222493298, 107144508620089458 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(1) has been checked by the direct computation of the Wiener index (using Maple). LINKS A. R. Ashrafi and M. Mirzagar, PI, Szeged and edge Szeged indices of an infinite family of nanostar dendrimers, Indian J. of Chemistry, 47A, 2008, 538-541. M. Rostami, M. Shabanian, and H. Moghanian, Some topological indices for theoretical study of two types of nanostar dendrimers, Digest J. of Nanomaterials and Biostructures, 7, No. 1, 2012, 247-252. J. Yang, F. Xia, and S. Chen, Second-order and third-order connectivity indices of an infinite family of dendrimer nanostars, Int. J. Contemp. Math. Sciences, 6, 2011, No. 5, 215-220. Index entries for linear recurrences with constant coefficients, signature (13,-64,148,-160,64). FORMULA a(n) = -55182 + 181020*2^n - 125640*4^n -42000*n*2^n +93600*n*4^n. G.f.: -6*x*(2112*x^4+10912*x^3-126044*x^2+14464*x+15783) / ((x-1)*(2*x-1)^2*(4*x-1)^2). - Colin Barker, Apr 01 2013 MAPLE a := proc (n) options operator, arrow: -55182+181020*2^n-125640*4^n+93600*4^n*n-42000*2^n*n end proc: seq(a(n), n = 1 .. 18); CROSSREFS Cf. A216123. Sequence in context: A252323 A030091 A128376 * A206411 A128389 A258420 Adjacent sequences:  A216119 A216120 A216121 * A216123 A216124 A216125 KEYWORD nonn,easy AUTHOR Emeric Deutsch, Mar 25 2013 STATUS approved

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Last modified January 23 19:17 EST 2022. Contains 350515 sequences. (Running on oeis4.)