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%I #13 Mar 29 2019 04:55:18
%S 1248,28184,264576,1799200,10428288,55146624,275248896,1321299200,
%T 6169283328,28218321664,127045890816,564885984000,2486370202368,
%U 10852804162304,47040516846336,202679222137600,868785296241408,3707414154572544,15758746697331456,66751342552544000,281870782248776448
%N The Wiener index of the nanostar dendrimer G_n , defined pictorially in the Golriz - Darafsheh - Khalifeh reference.
%H Vincenzo Librandi, <a href="/A221012/b221012.txt">Table of n, a(n) for n = 0..1000</a>
%H M. Golriz, M. R. Darafsheh, and M. H. Khalifeh, <a href="http://chalcogen.ro/1545_Golriz.pdf">The Wiener, Szeged and PI-indices of a phenylazomethine dendrimer</a>, Digest J. Nanomaterials and Biostructures, 6, No. 4, 2011, 1545-1549.
%F a(n) = -3328 - 2^n*(1820*n-18616) +4^n*(13520*n-14040) - see Theorem 4 in the Golriz et al. reference; it has a typo: change 181616 to 18616.
%F G.f.: 104*(12+115*x-211*x^2-204*x^3)/((1-x)*(1-2*x)^2*(1-4*x)^2). - _Bruno Berselli_, Dec 30 2012
%p a := proc (n) options operator, arrow: -3328-2^n*(1820*n-18616)+4^n*(13520*n-14040) end proc: seq(a(n), n = 0 .. 20);
%t CoefficientList[Series[104 *(12 + 115 * x - 211 * x^2 - 204 * x^3) / ((1 - x) * (1 - 2*x)^2 * (1 - 4*x)^2), {x, 0, 40}], x] (* _Vincenzo Librandi_, Dec 30 2012 *)
%Y Cf. A221013.
%K nonn,easy
%O 0,1
%A _Emeric Deutsch_, Dec 29 2012
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