A026561 Expansion of 1/((1-2x)(1-6x)(1-8x)(1-9x)).

1, 25, 405, 5405, 64661, 721725, 7683685, 79078285, 793624821, 7813101725, 75772440965, 726132366765, 6891899656981, 64900354798525, 607206802510245, 5650395374640845, 52342063252985141, 483011998315708125

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (25, -220, 780, -864).

Formula

a(n) = -2^n/21 +9*6^n -128*8^n/3 +243*9^n/7. - R. J. Mathar, Jun 30 2013

Crossrefs

Sequence in context: A238511 A028064 A028061 * A048908 A026391 A028044

Adjacent sequences: A026558 A026559 A026560 * A026562 A026563 A026564

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved