A025982 Expansion of 1/((1-2x)(1-4x)(1-9x)(1-12x)).

1, 27, 487, 7431, 103951, 1382439, 17812639, 224794647, 2797053391, 34460823111, 421597615231, 5131789410423, 62235068724271, 752703321093543, 9085382857597663, 109501083478899159, 1318301413026203791

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (27, -242, 816, -864).

Formula

a(0)=1, a(1)=27, a(2)=487, a(3)=7431, a(n)=27*a(n-1)-242*a(n-2)+ 816*a(n-3)- 864*a(n-4) -- From Harvey P. Dale, Jul 21 2012

a(n) = -2*2^n/35 +4*4^n/5 -243*9^n/35 +36*12^n/5. R. J. Mathar, Jun 20 2013

Mathematica

CoefficientList[Series[1/((1-2x)(1-4x)(1-9x)(1-12x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{27, -242, 816, -864}, {1, 27, 487, 7431}, 30] (* Harvey P. Dale, Jul 21 2012 *)

Crossrefs

Sequence in context: A081139 A020976 A024114 * A042408 A023946 A020971

Adjacent sequences: A025979 A025980 A025981 * A025983 A025984 A025985

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved