A055383 Expansion of (1+3*x+9*x^2+12*x^3+11*x^4+3*x^5+x^6)/((1-x)^2*(1-x^2)^2*(1-x^3)).

1, 5, 20, 54, 123, 239, 428, 706, 1107, 1653, 2386, 3332, 4543, 6049, 7910, 10162, 12873, 16083, 19870, 24278, 29393, 35265, 41988, 49616, 58253, 67957, 78840, 90966, 104455, 119375, 135856, 153970, 173855, 195589, 219318, 245124

Offset

0,2

References

R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see Problem 6.28(c), y_4.

Links

Table of n, a(n) for n=0..35.

Index entries for linear recurrences with constant coefficients, signature (2,1,-3,-1,1,3,-1,-2,1).

Mathematica

CoefficientList[Series[(1+3x+9x^2+12x^3+11x^4+3x^5+x^6)/((1-x)^2(1-x^2)^2(1-x^3)), {x, 0, 40}], x] (* Harvey P. Dale, Jun 04 2019 *)

Crossrefs

Sequence in context: A006010 A270334 A008524 * A090133 A351931 A366057

Adjacent sequences: A055380 A055381 A055382 * A055384 A055385 A055386

Keyword

nonn

Author

N. J. A. Sloane, Jul 05 2000

Status

approved