A198700 11*10^n-1.

10, 109, 1099, 10999, 109999, 1099999, 10999999, 109999999, 1099999999, 10999999999, 109999999999, 1099999999999, 10999999999999, 109999999999999, 1099999999999999, 10999999999999999, 109999999999999999

Offset

0,1

Links

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

Index entries for linear recurrences with constant coefficients, signature (11,-10).

Formula

a(n) = 10*a(n-1)+9. a(n) = 11*a(n-1)-10*a(n-2), n>1.

G.f. ( 10-x ) / ( (10*x-1)*(x-1) ). - R. J. Mathar, Oct 29 2011

Mathematica

(11 10^Range[0, 20])-1 (* or  *) LinearRecurrence[{11, -10}, {10, 109}, 20] (* Harvey P. Dale, Nov 29 2020 *)

Prog

(Magma) [11*10^n-1: n in [0..30]]

Crossrefs

Cf. A002283, A066007, A109002.

Sequence in context: A024527 A291894 A217322 * A320094 A267280 A015591

Adjacent sequences: A198697 A198698 A198699 * A198701 A198702 A198703

Keyword

nonn,easy

Author

Vincenzo Librandi, Oct 29 2011

Status

approved