A036548 a(n) = T(7,n), array T given by A048471.

1, 129, 513, 1665, 5121, 15489, 46593, 139905, 419841, 1259649, 3779073, 11337345, 34012161, 102036609, 306109953, 918329985, 2754990081, 8264970369, 24794911233, 74384733825, 223154201601, 669462604929, 2008387814913

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (4,-3).

Formula

a(n) = 64*3^n - 63. - Ralf Stephan, Feb 17 2004

From Vincenzo Librandi, Nov 11 2011: (Start)

a(n) = 3*a(n-1) + 126.

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

G.f.: (1+125*x)/((1-x)*(1-3*x)). (End)

Prog

(Magma) [64*3^n-63: n in [0..30]]; // Vincenzo Librandi, Nov 11 2011

Crossrefs

n-th difference of a(n), a(n-1), ..., a(0) is 2^(n+6) for n=1, 2, 3, ...

Sequence in context: A250814 A249679 A250750 * A046286 A341552 A251095

Adjacent sequences: A036545 A036546 A036547 * A036549 A036550 A036551

Keyword

nonn,easy

Author

Clark Kimberling

Status

approved