A024127 a(n) = 11^n-1.

0, 10, 120, 1330, 14640, 161050, 1771560, 19487170, 214358880, 2357947690, 25937424600, 285311670610, 3138428376720, 34522712143930, 379749833583240, 4177248169415650, 45949729863572160, 505447028499293770, 5559917313492231480, 61159090448414546290, 672749994932560009200

Offset

0,2

Comments

In base 11 these are 0, A, AA, AAA, ... - David Rabahy, Dec 12 2016

Links

Table of n, a(n) for n=0..20.

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

Formula

From Mohammad K. Azarian, Jan 14 2009: (Start)

G.f.: 1/(1-11*x)-1/(1-x).

E.g.f.: e^(11*x)-e^x. (End)

a(n) = 11*a(n-1)+10 for n>0, a(0)=0. - Vincenzo Librandi, Nov 19 2010

a(n) = Sum_{i=1..n} 10^i*binomial(n,n-i) for n>0, a(0)=0. - Bruno Berselli, Nov 11 2015

a(n) = A001020(n) - 1. - Sean A. Irvine, Jun 19 2019

Mathematica

LinearRecurrence[{12, -11}, {0, 10}, 18] (* Ray Chandler, Aug 26 2015 *)

Prog

(PARI) a(n)=11^n-1 \\ Charles R Greathouse IV, Dec 12 2016

Crossrefs

Cf. A001020.

Sequence in context: A300522 A252874 A182605 * A005949 A027568 A318495

Adjacent sequences: A024124 A024125 A024126 * A024128 A024129 A024130

Keyword

nonn,easy,changed

Author

N. J. A. Sloane

Extensions

More terms from Michel Marcus, Jul 12 2026

Status

approved