A199030 a(n) = 10*11^n-1.

9, 109, 1209, 13309, 146409, 1610509, 17715609, 194871709, 2143588809, 23579476909, 259374246009, 2853116706109, 31384283767209, 345227121439309, 3797498335832409, 41772481694156509, 459497298635721609, 5054470284992937709

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..900

Index entries for linear recurrences with constant coefficients, signature (12,-11).

Formula

a(n) = 11*a(n-1)+10.

a(n) = 12*a(n-1)-11*a(n-2).

G.f.: (9+x)/((1-x)*(1-11*x)). - Bruno Berselli, Nov 03 2011

Prog

(Magma) [10*11^n-1: n in [0..20]];

Crossrefs

Sequence in context: A058421 A267795 A128876 * A288692 A358601 A349335

Adjacent sequences: A199027 A199028 A199029 * A199031 A199032 A199033

Keyword

nonn,easy

Author

Vincenzo Librandi, Nov 03 2011

Status

approved