A012864 Take every 5th term of Padovan sequence A000931, beginning with the first term.

1, 1, 3, 12, 49, 200, 816, 3329, 13581, 55405, 226030, 922111, 3761840, 15346786, 62608681, 255418101, 1042002567, 4250949112, 17342153393, 70748973084, 288627200960, 1177482265857, 4803651498529, 19596955630177

Offset

0,3

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (5, -4, 1).

Formula

a(n+3) = 5*a(n+2) - 4*a(n+1) + a(n).

O.g.f.: (1-4x+2x^2)/(1-5x+4x^2-x^3). a(n+1)=A012772(n). - R. J. Mathar, May 28 2008

Mathematica

LinearRecurrence[{5, -4, 1}, {1, 1, 3}, 30] (* Vincenzo Librandi, Apr 18 2012 *)

Prog

(Magma) I:=[1, 1, 3]; [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

Crossrefs

Cf. A012855.

Sequence in context: A037758 A037646 A012772 * A382122 A045890 A049673

Adjacent sequences: A012861 A012862 A012863 * A012865 A012866 A012867

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved