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 A227700 The hyper-Wiener index of the nanostar dendrimer defined pictorially in the Ashrafi et al. reference. 1
 299671, 1624639, 9938719, 60310495, 352063711, 1970086879, 10608950239, 55279894495, 280190685151, 1387684298719, 6740446216159, 32207067824095, 151750499712991, 706442679304159, 3254507926208479, 14856796917219295, 67277314593931231, 302489552025567199 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS a(1) has been checked by the direct computation of the Wiener index (using Maple). LINKS A. R. Ashrafi, A. Karbasioun, and M. V. Diudea, Computing Wiener and detour indices of a new type of nanostar dendrimers, MATCH Commun. Math. Comput. Chem. 65, 2011, 193-200. FORMULA a(n) = 16351 + 2^n*(26400*n^2 + 52080*n + 40656) + 4^n*(57600*n^2 + 42240*n + 242664). G.f.: (299671 - 4069110*x + 24021228*x^2 -75420072*x^3 + 131188512*x^4 -120811392*x^5 + 45232640*x^6)/((1-x)*(1-2*x)^3*(1-4*x)^3). MAPLE a := proc (n) options operator, arrow: 16351+2^n*(26400*n^2+52080*n+40656)+4^n*(57600*n^2+42240*n+242664) end proc: seq(a(n), n = 0 .. 22); MATHEMATICA nn:=19; CoefficientList[Series[(299671 - 4069110*x + 24021228*x^2 -75420072*x^3 + 131188512*x^4 -120811392*x^5 + 45232640*x^6)/((1-x)*(1-2*x)^3*(1-4*x)^3), {x, 0, nn}], x] (* Georg Fischer, Apr 17 2020 *) CROSSREFS Cf. A227699. Sequence in context: A254186 A253798 A022246 * A050257 A283209 A113939 Adjacent sequences:  A227697 A227698 A227699 * A227701 A227702 A227703 KEYWORD nonn,easy AUTHOR Emeric Deutsch, Jul 21 2013 STATUS approved

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Last modified October 22 22:22 EDT 2020. Contains 337962 sequences. (Running on oeis4.)