A028122 Expansion of 1/((1-4x)(1-5x)(1-8x)(1-11x)).

1, 28, 505, 7500, 100161, 1254588, 15084745, 176531500, 2028331921, 23012251548, 258784204185, 2892049106700, 32177076653281, 356869970102908, 3948976130302825, 43626137399621100, 481387456885736241

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (28,-279,1172,-1760)

Formula

From Vincenzo Librandi, Mar 17 2011: (Start)

a(n) = 28*a(n-1) - 279*a(n-2) + 1172*a(n-3) - 1760*a(n-4), n >= 4.

a(n) = 19*a(n-1) - 88*a(n-2) + 5^(n+1) - 4^(n+1), n >= 2. (End)

a(n) = -4^(n+2)/7 - 2*8^(n+2)/9 + 11^(n+3)/126 + 5^(n+3)/18. - R. J. Mathar, Mar 18 2011

Mathematica

CoefficientList[Series[1/((1-4x)(1-5x)(1-8x)(1-11x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{28, -279, 1172, -1760}, {1, 28, 505, 7500}, 30] (* Harvey P. Dale, Apr 01 2013 *)

Crossrefs

Sequence in context: A028133 A042516 A028083 * A028081 A028009 A028119

Adjacent sequences: A028119 A028120 A028121 * A028123 A028124 A028125

Keyword

nonn

Author

N. J. A. Sloane

Status

approved