A198769 (9*5^n-1)/4.

2, 11, 56, 281, 1406, 7031, 35156, 175781, 878906, 4394531, 21972656, 109863281, 549316406, 2746582031, 13732910156, 68664550781, 343322753906, 1716613769531, 8583068847656, 42915344238281, 214576721191406, 1072883605957031

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

G.f.: (2-x)/(5*x^2-6*x+1) [From Harvey P. Dale, May 07 2012]

Mathematica

(9*5^Range[0, 30]-1)/4 (* or *) LinearRecurrence[{6, -5}, {2, 11}, 30] (* Harvey P. Dale, May 07 2012 *)

Prog

(Magma) [(9*5^n-1)/4: n in [0..30]]

Crossrefs

Cf. A024049, A057651, A081655.

Sequence in context: A306753 A306860 A212388 * A037554 A106804 A361219

Adjacent sequences: A198766 A198767 A198768 * A198770 A198771 A198772

Keyword

nonn,easy

Author

Vincenzo Librandi, Oct 30 2011

Status

approved