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a(n) = 75*2^n - 38.
4

%I #26 Jul 31 2024 09:07:33

%S 37,112,262,562,1162,2362,4762,9562,19162,38362,76762,153562,307162,

%T 614362,1228762,2457562,4915162,9830362,19660762,39321562,78643162,

%U 157286362,314572762,629145562,1258291162,2516582362,5033164762,10066329562,20132659162,40265318362,80530636762,161061273562

%N a(n) = 75*2^n - 38.

%C a(n) is the number of vertices of the nanostar dendrimer NS[n] from the Mirzargar reference.

%H Colin Barker, <a href="/A304612/b304612.txt">Table of n, a(n) for n = 0..1000</a>

%H M. Mirzargar, <a href="http://match.pmf.kg.ac.rs/electronic_versions/Match62/n2/match62n2_363-370.pdf">PI, Szeged and edge Szeged polynomials of a dendrimer nanostar</a>, MATCH, Commun. Math. Comput. Chem. 62, 2009, 363-370.

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (3,-2).

%F G.f.: (37 + x)/((1 - x)*(1 - 2*x)). - _Bruno Berselli_, May 17 2018

%p seq(75*2^n-38, n = 0 .. 40);

%t 75*2^Range[0, 50] - 38 (* _Paolo Xausa_, Jul 31 2024 *)

%o (PARI) a(n) = 75*2^n - 38; \\ _Altug Alkan_, May 17 2018

%o (PARI) Vec((37 + x)/((1 - x)*(1 - 2*x)) + O(x^40)) \\ _Colin Barker_, May 23 2018

%Y Cf. A304613, A304614, A304615.

%K nonn,easy

%O 0,1

%A _Emeric Deutsch_, May 16 2018