A028191 Expansion of 1/((1-5x)(1-8x)(1-9x)(1-11x)).

1, 33, 690, 11690, 175371, 2432283, 31956940, 403804980, 4956450741, 59506980533, 702298022790, 8177594495070, 94207230682111, 1076026739628783, 12205736906550240, 137681865037361960

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (33,-399,2087,-3960).

Formula

a(n) = 20*a(n-1) - 99*a(n-2) + (8^(n+1) - 5^(n+1))/3, n >= 2. - Vincenzo Librandi, Mar 12 2011

a(n) = (8^(n+4) - 9^(n+4) + 2*11^(n+3) - 5^(n+3))/72. - Bruno Berselli, Mar 12 2010

a(0)=1, a(1)=33, a(2)=690, a(3)=11690, a(n) = 33*a(n-1) - 399*a(n-2) + 2087*a(n-3) - 3960*a(n-4). - Harvey P. Dale, May 15 2011

Mathematica

CoefficientList[Series[1/((1-5x)(1-8x)(1-9x)(1-11x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{33, -399, 2087, -3960}, {1, 33, 690, 11690}, 30] (* Harvey P. Dale, May 15 2011 *)

Prog

(Magma) I:=[1, 33, 690, 11690]; [n le 4 select I[n] else 33*Self(n-1)-399*Self(n-2)+2087*Self(n-3)-3960*Self(n-4): n in [1..20]]; // Vincenzo Librandi, May 20 2012

Crossrefs

Sequence in context: A164761 A028210 A028205 * A028203 A028187 A028186

Adjacent sequences: A028188 A028189 A028190 * A028192 A028193 A028194

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved