A025972 Expansion of 1/((1-2x)(1-4x)(1-7x)(1-9x)).

1, 22, 317, 3806, 41421, 424974, 4198189, 40430302, 382529741, 3573890606, 33084972141, 304212832638, 2783085627661, 25364095795918, 230491675046573, 2089930913053214, 18917927670786381, 171021229569836910

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (22,-167,506,-504).

Formula

G.f.: 1/((1-2x)*(1-4x)*(1-7x)*(1-9x)).

a(n) = -4*2^n/35 +32*4^n/15 -343*7^n/30 +729*9^n/70. - R. J. Mathar, Jun 20 2013

a(n) = 22*a(n-1) - 167*a(n-2) + 506*a(n-3) - 504*a(n-4). - Wesley Ivan Hurt, May 26 2024

Mathematica

CoefficientList[Series[1/((1-2x)(1-4x)(1-7x)(1-9x)), {x, 0, 30}], x] (* Harvey P. Dale, Sep 21 2020 *)

Crossrefs

Sequence in context: A025988 A267132 A023949 * A028029 A022453 A025968

Adjacent sequences: A025969 A025970 A025971 * A025973 A025974 A025975

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved