A016325 Expansion of 1/((1-2x)(1-10x)(1-11x)).

1, 23, 377, 5395, 71841, 915243, 11317657, 136994195, 1631936081, 19201296763, 223714264137, 2585856904995, 29694425953921, 339138685491083, 3855525540397817, 43660780944367795, 492768590388029361

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (23,-152,220)

Formula

From Zerinvary Lajos, Jun 05 2009 [corrected by R. J. Mathar, Mar 14 2011]: (Start)

a(n) = 11^(n+2)/9 + 2^(n-1)/9 - 25*10^n/2.

a(n) = A016135(n+1) - A016134(n+1). (End)

a(n) = 21*a(n-1) - 110*a(n-2) + 2^n. - Vincenzo Librandi, Oct 09 2011

Mathematica

CoefficientList[Series[1/((1 - 2 x) (1 - 10 x) (1 - 11 x)), {x, 0, 16}], x] (* Michael De Vlieger, Jan 31 2018 *)

Prog

(Sage) [(11^n - 2^n)/9-(10^n - 2^n)/8 for n in range(2, 19)] # Zerinvary Lajos, Jun 05 2009
(Magma) [(2*11^(n+2) +2^n-225*10^n)/18 : n in [0..20]]; // Vincenzo Librandi, Oct 09 2011
(PARI) Vec(1/((1-2*x)*(1-10*x)*(1-11*x))+O(x^99)) \\ Charles R Greathouse IV, Sep 23 2012

Crossrefs

Cf. A016134, A016135.

Sequence in context: A018091 A021279 A018071 * A016324 A264321 A285234

Adjacent sequences: A016322 A016323 A016324 * A016326 A016327 A016328

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved