A199418 3*7^n+1.

4, 22, 148, 1030, 7204, 50422, 352948, 2470630, 17294404, 121060822, 847425748, 5931980230, 41523861604, 290667031222, 2034669218548, 14242684529830, 99698791708804, 697891541961622, 4885240793731348, 34196685556119430

Offset

0,1

Links

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

Index entries for linear recurrences with constant coefficients, signature (8,-7).

Formula

a(n) = 7*a(n-1)-6.

a(n) = 8*a(n-1)-7*a(n-2).

G.f.: 2*(2-5*x)/((1-x)*(1-7*x)).

Mathematica

LinearRecurrence[{8, -7}, {4, 22}, 20] (* Harvey P. Dale, Dec 29 2018 *)

Prog

(Magma) [3*7^n+1: n in [0..30]];

Crossrefs

Sequence in context: A369617 A121394 A005039 * A112898 A368733 A253095

Adjacent sequences: A199415 A199416 A199417 * A199419 A199420 A199421

Keyword

nonn,easy

Author

Vincenzo Librandi, Nov 06 2011

Status

approved