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%I #16 Sep 08 2022 08:46:21
%S 12,132,372,852,1812,3732,7572,15252,30612,61332,122772,245652,491412,
%T 982932,1965972,3932052,7864212,15728532,31457172,62914452,125829012,
%U 251658132,503316372,1006632852,2013265812,4026531732,8053063572,16106127252,32212254612,64424509332,128849018772,257698037652
%N a(n) = 120*2^n - 108.
%C a(n) is the number of vertices in the nanostar dendrimer G[n], shown pictorially as NSD[n] in the Rostami et al. reference (Fig. 2).
%H Colin Barker, <a href="/A305261/b305261.txt">Table of n, a(n) for n = 0..1000</a>
%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_02">Index entries for linear recurrences with constant coefficients</a>, signature (3,-2).
%F From _Colin Barker_, May 31 2018: (Start)
%F G.f.: 12*(1 + 8*x) / ((1 - x)*(1 - 2*x)).
%F a(n) = 3*a(n-1) - 2*a(n-2) for n > 1.
%F (End)
%p seq(120*2^n-108, n = 0 .. 40);
%o (PARI) Vec(12*(1 + 8*x) / ((1 - x)*(1 - 2*x) + O(x^40))) \\ _Colin Barker_, May 31 2018
%o (Magma) [120*2^n - 108 : n in [0..30]]; // _Wesley Ivan Hurt_, Apr 23 2021
%Y Cf. A305262, A305263, A305264.
%K nonn,easy
%O 0,1
%A _Emeric Deutsch_, May 29 2018
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