A183188 a(n) = 3*a(n-1) + a(n-3) with a(0)=1, a(1)=2, a(2)=6.

1, 2, 6, 19, 59, 183, 568, 1763, 5472, 16984, 52715, 163617, 507835, 1576220, 4892277, 15184666, 47130218, 146282931, 454033459, 1409230595, 4373974716, 13575957607, 42137103416, 130785284964, 405931812499, 1259932540913, 3910582907703, 12137680535608

Offset: 0

Author

Philippe Deléham, Dec 14 2011

Keywords

• easy
• nonn

Links

• Index entries for linear recurrences with constant coefficients, signature (3,0,1).

Crossrefs

Cf. A052541, A193723.

Programs

Mathematica

LinearRecurrence[{3,0,1},{1,2,6},30] (* Harvey P. Dale, Nov 02 2024 *)

Formula

G.f.: (1-x)/(1-3*x-x^3).

a(n) = A052541(n) - A051541(n-1). - R. J. Mathar, Dec 15 2011

Extensions

Corrected by R. J. Mathar, Dec 15 2011