A198847 a(n) = 10*6^n - 1.

9, 59, 359, 2159, 12959, 77759, 466559, 2799359, 16796159, 100776959, 604661759, 3627970559, 21767823359, 130606940159, 783641640959, 4701849845759, 28211099074559, 169266594447359, 1015599566684159, 6093597400104959, 36561584400629759

Offset

0,1

Comments

The subsequence of primes begins: 59, 359, 12959, 3627970559, 130606940159, 105567144438288796176937144911353144349827436380159, ... associated with exponents n = 1, 2, 4, 11, 13, 63, 71, ... - Jonathan Vos Post, Oct 31 2011

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) + 5.

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

G.f.: ( 9-4*x ) / ( (6*x-1)*(x-1) ). - R. J. Mathar, Oct 31 2011

Mathematica

10(6^Range[20]) - 1 (* Alonso del Arte, Oct 31 2011 *)

Prog

(Magma) [10*6^n-1: n in [0..30]]

Crossrefs

Sequence in context: A027249 A026717 A231228 * A059356 A039929 A099333

Adjacent sequences: A198844 A198845 A198846 * A198848 A198849 A198850

Keyword

nonn,easy

Author

Vincenzo Librandi, Oct 31 2011

Status

approved