A028205 Expansion of 1/((1-6x)(1-7x)(1-9x)(1-11x)).

1, 33, 688, 11598, 172879, 2380371, 31036006, 389148576, 4740682837, 56509956789, 662486064604, 7666900074834, 87835709417275, 998290939845687, 11274360941128882, 126686827598516772, 1417790522653118593

Offset

0,2

Links

Table of n, a(n) for n=0..16.

Index entries for linear recurrences with constant coefficients, signature (33,-401,2127,-4158)

Formula

a(n) = 20*a(n-1) - 99*a(n-2) + 7^(n+1) - 6^(n+1), n >= 2. - Vincenzo Librandi, Mar 13 2011

a(n) = -3*9^(n+2)/4 + 11^(n+3)/40 + 7^(n+3)/8 - 2*6^(n+2)/5. - R. J. Mathar, Mar 18 2011

Mathematica

CoefficientList[Series[1/((1-6x)(1-7x)(1-9x)(1-11x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{33, -401, 2127, -4158}, {1, 33, 688, 11598}, 30] (* Harvey P. Dale, Sep 12 2016 *)

Crossrefs

Sequence in context: A083956 A164761 A028210 * A028191 A028203 A028187

Adjacent sequences: A028202 A028203 A028204 * A028206 A028207 A028208

Keyword

nonn

Author

N. J. A. Sloane

Status

approved