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%I #19 May 16 2018 11:45:36
%S 96,234,510,1062,2166,4374,8790,17622,35286,70614,141270,282582,
%T 565206,1130454,2260950,4521942,9043926,18087894,36175830,72351702,
%U 144703446,289406934,578813910,1157627862,2315255766,4630511574,9261023190,18522046422,37044092886,74088185814,148176371670,296352743382,592705486806
%N a(n) = 69*2^n - 42 (n>=1).
%C a(n) = number of edges of the dendrimer nanostar NS2[n], defined pictorially in Fig. 2 of the Madanshekaf reference.
%D A. Madanshekaf, The Randic index of some dendrimer nanostars, J. Appl. Math. & Informatics, 29, No. 5-6, 2011, 1075-1080.
%H Colin Barker, <a href="/A304510/b304510.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (3,-2).
%F From _Colin Barker_, May 15 2018: (Start)
%F G.f.: 6*x*(16 - 9*x) / ((1 - x)*(1 - 2*x)).
%F a(n) = 3*a(n-1) - 2*a(n-2) for n>2.
%F (End)
%p seq(69*2^n-42, n = 1 .. 40);
%t Array[69*2^# - 42 &, 33] (* _Michael De Vlieger_, May 14 2018 *)
%o (GAP) List([1..40],n->69*2^n-42); # _Muniru A Asiru_, May 15 2018
%o (PARI) Vec(6*x*(16 - 9*x) / ((1 - x)*(1 - 2*x)) + O(x^40)) \\ _Colin Barker_, May 15 2018
%Y Cf. A304509, A304511, A304512.
%K nonn,easy
%O 1,1
%A _Emeric Deutsch_, May 14 2018