A091691 a(n) = (10^(n-1)-1) * (n-10) / 9.

1, 0, -8, -77, -666, -5555, -44444, -333333, -2222222, -11111111, 0, 1111111111, 22222222222, 333333333333, 4444444444444, 55555555555555, 666666666666666, 7777777777777777, 88888888888888888, 999999999999999999, 11111111111111111110, 122222222222222222221

Offset

0,3

Links

Table of n, a(n) for n=0..21.

Index entries for linear recurrences with constant coefficients, signature (22,-141,220,-100).

Formula

G.f.: ( 1+133*x^2-121*x^3-22*x ) / ( (10*x-1)^2*(x-1)^2 ). - R. J. Mathar, Feb 14 2015

Mathematica

LinearRecurrence[{22, -141, 220, -100}, {1, 0, -8, -77}, 30] (* Harvey P. Dale, Jun 24 2018 *)

Crossrefs

Cf. A091686.

Sequence in context: A105429 A225348 A091686 * A024103 A187638 A092661

Adjacent sequences: A091688 A091689 A091690 * A091692 A091693 A091694

Keyword

easy,sign

Author

Paul Barry, Jan 29 2004

Status

approved