A133383 10 followed by 2n 9's.

10, 1099, 109999, 10999999, 1099999999, 109999999999, 10999999999999, 1099999999999999, 109999999999999999, 10999999999999999999, 1099999999999999999999, 109999999999999999999999, 10999999999999999999999999, 1099999999999999999999999999, 109999999999999999999999999999

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (101,-100).

Formula

a(n) = 11*10^(2*n) - 1. - Vincenzo Librandi, Aug 10 2011

From Elmo R. Oliveira, Jun 12 2025: (Start)

G.f.: (10 + 89*x)/((100*x-1)*(x-1)).

E.g.f.: exp(x)*(11*exp(99*x) - 1).

a(n) = 101*a(n-1) - 100*a(n-2). (End)

Mathematica

11*10^(2*Range[15]) - 1 (* Paolo Xausa, Jun 13 2025 *)

Prog

(Magma) [11*10^(2*n)-1: n in [0..15]]; // Vincenzo Librandi, Aug 10 2011

Crossrefs

Sequence in context: A119045 A339714 A069886 * A268229 A307723 A071672

Adjacent sequences: A133380 A133381 A133382 * A133384 A133385 A133386

Keyword

nonn,base,easy

Author

Paul Curtz, Oct 29 2007

Status

approved