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%I #19 Jan 12 2024 07:07:39
%S 1,3,12,49,200,816,3329,13581,55405,226030,922111,3761840,15346786,
%T 62608681,255418101,1042002567,4250949112,17342153393,70748973084,
%U 288627200960,1177482265857,4803651498529,19596955630177
%N Take every 5th term of Padovan sequence A000931, beginning with the sixth term.
%H Vincenzo Librandi, <a href="/A012772/b012772.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (5, -4, 1).
%F a(n+3) = 5*a(n+2) - 4*a(n+1) + a(n).
%F G.f.: (1-x)^2/(1-5*x+4*x^2-x^3). - _Colin Barker_, Feb 02 2012
%t CoefficientList[Series[(1-x)^2/(1-5*x+4*x^2-x^3),{x,0,33}],x] (* _Vincenzo Librandi_, Apr 18 2012 *)
%o (Magma) I:=[1, 3, 12]; [n le 3 select I[n] else 5*Self(n-1)-4*Self(n-2)+Self(n-3): n in [1..30]]; // _Vincenzo Librandi_, Apr 18 2012
%Y Cf. A012781 (partial sums).
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_.
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