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%I #24 Sep 08 2022 08:44:38
%S 18,5832,1889568,612220032,198359290368,64268410079232,
%T 20822964865671168,6746640616477458432,2185911559738696531968,
%U 708235345355337676357632,229468251895129407139872768
%N a(n) = 18^(2*n + 1).
%H Vincenzo Librandi, <a href="/A013723/b013723.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 (324).
%F From _Philippe Deléham_, Nov 28 2008: (Start)
%F a(n) = 324*a(n-1); a(0)=18.
%F G.f.: 18/(1-324*x). (End)
%p seq(18^(2*n+1),n=0..10); # _Nathaniel Johnston_, Jun 25 2011
%t 18^(2*Range[0,20]+1) (* or *) NestList[324#&,18,20] (* _Harvey P. Dale_, Sep 28 2021 *)
%o (Magma) [18^(2*n+1): n in [0..15]]; // _Vincenzo Librandi_, Jun 26 2011
%o (PARI) a(n)=18^(2*n+1) \\ _Charles R Greathouse IV_, Jul 11 2016
%Y Bisection of A001027 (18^n).
%Y Cf. A013708-A013722, A013724-A013729.
%K nonn,easy
%O 0,1
%A _N. J. A. Sloane_