A198849 a(n) = (11*6^n - 1)/5.

2, 13, 79, 475, 2851, 17107, 102643, 615859, 3695155, 22170931, 133025587, 798153523, 4788921139, 28733526835, 172401161011, 1034406966067, 6206441796403, 37238650778419, 223431904670515, 1340591428023091, 8043548568138547

Offset

0,1

Links

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

Index entries for linear recurrences with constant coefficients, signature (7,-6).

Formula

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

a(n) = 7*a(n-1) - 6*a(n-2), n > 1.

G.f.: ( 2-x ) / ( (6*x-1)*(x-1) ). - R. J. Mathar, Oct 31 2011

Prog

(Magma) [(11*6^n-1)/5: n in [0..30]]

Crossrefs

Sequence in context: A037732 A090187 A212390 * A037555 A135167 A271475

Adjacent sequences: A198846 A198847 A198848 * A198850 A198851 A198852

Keyword

nonn,easy

Author

Vincenzo Librandi, Oct 31 2011

Status

approved