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%I #23 Sep 08 2022 08:44:38
%S 729,4782969,31381059609,205891132094649,1350851717672992089,
%T 8862938119652501095929,58149737003040059690390169,
%U 381520424476945831628649898809,2503155504993241601315571986085849,16423203268260658146231467800709255289
%N a(n) = 9^(4*n + 3).
%H Vincenzo Librandi, <a href="/A013791/b013791.txt">Table of n, a(n) for n = 0..200</a>
%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>
%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (6561).
%F From _Philippe Deléham_, Dec 07 2008: (Start)
%F a(n) = 6561*a(n-1); a(0)=729.
%F G.f.: 729/(1-6561*x).
%F a(n) = 81*A013790(n). (End)
%t 9^(4*Range[0,20]+3) (* or *) NestList[6561#&,729,20] (* _Harvey P. Dale_, Jul 30 2021 *)
%o (Magma) [9^(4*n+3): n in [0..15]]; // _Vincenzo Librandi_, Jun 28 2011
%o (PARI) a(n)=9^(4*n+3) \\ _Charles R Greathouse IV_, Jul 11 2016
%Y Subsequence of A001019.
%K nonn,easy
%O 0,1
%A _N. J. A. Sloane_
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