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%I #23 Nov 15 2016 03:02:30
%S 8580,751148,13742092,145113196,1166551916,7991214060,49348860396,
%T 283593693164,1546469947372,8104770527212,41179270758380,
%U 204101468659692,991328100589548,4734560147021804,22293506692030444,103708270251417580,477422926327128044
%N The hyper-Wiener index of the nanostar dendrimer NSC_5C_6[n], defined pictorially in the A. R. Ashrafi et al. reference and in the M. Rostami et al. reference.
%C a(2) has been checked by the direct computation of the Wiener index (using Maple).
%C The given references do not consider the hyper-Wiener index.
%H Colin Barker, <a href="/A221053/b221053.txt">Table of n, a(n) for n = 1..1000</a>
%H A. R. Ashrafi and P. Nikzad, <a href="http://www.chalcogen.ro/1Ashrafi-Nikzad.pdf">Szeged index of nanostar dendrimers</a>, Digest J. of Nanomaterials and Biostructures, 4, No. 1, 2009, 155-157.
%H M. Rostami, M. Shabanian, and H. Moghanian, <a href="http://www.chalcogen.ro/247_Rostami.pdf">Some topological indices for theoretical study of two types of nanostar dendrimers</a>, Digest J. of Nanomaterials and Biostructures, 7, No. 1, 2012, 247-252.
%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (19,-150,636,-1560,2208,-1664,512).
%F a(n) = 204780 - 1311272*2^n + 1106480*4^n + 360*2^n*n^2 + 129600*4^n*n^2 + 7852*2^n*n - 633600*4^n*n.
%F G.f.: 4*x*(1536*x^6-1645696*x^5-1592416*x^4+2192808*x^3-189320*x^2 -147032*x -2145) / ((x-1)*(2*x-1)^3*(4*x-1)^3). - _Colin Barker_, Apr 01 2013
%p a := proc(n) 204780-1311272*2^n+1106480*4^n+360*2^n*n^2+129600*4^n*n^2 +7852*2^n*n-633600*4^n*n end proc: seq(a(n), n = 1 .. 17);
%o (PARI) Vec(4*x*(1536*x^6-1645696*x^5-1592416*x^4+2192808*x^3-189320*x^2 -147032*x-2145)/((x-1)*(2*x-1)^3*(4*x-1)^3) + O(x^20)) \\ _Colin Barker_, Jun 04 2016
%Y Cf. A221052.
%K nonn,easy
%O 1,1
%A _Emeric Deutsch_, Mar 28 2013
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