A025967 Expansion of 1/((1-2x)(1-4x)(1-6x)(1-9x)).

1, 21, 289, 3321, 34705, 343257, 3282913, 30740457, 283960369, 2599944633, 23667405697, 214622461833, 1941330570193, 17530479823449, 158125883415841, 1425244488222249, 12839878208747377, 115635005126816505

Offset

0,2

Links

Table of n, a(n) for n=0..17.

Index entries for linear recurrences with constant coefficients, signature (21, -152, 444, -432).

Formula

a(n) = (8*9^(n+3)-35*6^(n+3)+42*4^(n+3)-15*2^(n+3))/840. - Yahia Kahloune, May 24 2013

Crossrefs

Sequence in context: A316924 A317042 A317696 * A022452 A183731 A101703

Adjacent sequences: A025964 A025965 A025966 * A025968 A025969 A025970

Keyword

nonn,easy

Author

N. J. A. Sloane.

Status

approved