A025991 Expansion of 1/((1-2x)(1-5x)(1-6x)(1-12x)).

1, 25, 417, 5909, 77369, 972381, 11958289, 145367893, 1756276137, 21149737037, 254259660161, 3053974195077, 36665246878105, 440090336260093, 5281738449973233, 63384838751399861, 760642183440232073

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (25, -208, 684, -720).

Formula

a(0)=1, a(1)=25, a(2)=417, a(3)=5909, a(n)=25*a(n-1)- 208*a(n-2)+ 684*a(n-3)-720*a(n-4). - Harvey P. Dale, May 20 2013

a(n) = -2^n/15 +125*5^n/21 -9*6^n/1 +144*12^n/35. R. J. Mathar, Jun 20 2013

Mathematica

CoefficientList[Series[1/((1-2x)(1-5x)(1-6x)(1-12x)), {x, 0, 20}], x] (* or *) LinearRecurrence[{25, -208, 684, -720}, {1, 25, 417, 5909}, 20] (* Harvey P. Dale, May 20 2013 *)

Crossrefs

Sequence in context: A102072 A022845 A023952 * A022628 A020838 A025975

Adjacent sequences: A025988 A025989 A025990 * A025992 A025993 A025994

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved