A199315 (11*5^n+1)/2.

6, 28, 138, 688, 3438, 17188, 85938, 429688, 2148438, 10742188, 53710938, 268554688, 1342773438, 6713867188, 33569335938, 167846679688, 839233398438, 4196166992188, 20980834960938, 104904174804688, 524520874023438, 2622604370117188

Offset

0,1

Links

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

Index entries for linear recurrences with constant coefficients, signature (6,-5).

Formula

a(n) = 5*a(n-1)-2.

a(n) = 6*a(n-1)-5*a(n-2).

G.f.: 2*(3-4*x)/((1-x)*(1-5*x)).

Mathematica

(11 5^Range[0, 40]+1)/2 (* or *) LinearRecurrence[{6, -5}, {6, 28}, 40] (* Harvey P. Dale, Aug 30 2016 *)

Prog

(Magma) [(11*5^n+1)/2: n in [0..30]];

Crossrefs

Sequence in context: A368574 A208439 A108051 * A001599 A335316 A335317

Adjacent sequences: A199312 A199313 A199314 * A199316 A199317 A199318

Keyword

nonn,easy

Author

Vincenzo Librandi, Nov 05 2011

Status

approved