A025998 Expansion of 1/((1-2x)*(1-5x)*(1-8x)*(1-10x)).

1, 25, 409, 5565, 68481, 792645, 8815129, 95390845, 1012475761, 10596550965, 109756131849, 1127967674925, 11523334499041, 117184641488485, 1187466959384569, 11999684812451805, 120997224186474321, 1217976521926061205, 12243805817579757289, 122950414751494265485, 1233603159066234897601

Offset

0,2

Links

Table of n, a(n) for n=0..20.

Index entries for linear recurrences with constant coefficients, signature (25,-216,740,-800).

Formula

a(n) = -2^n/18 +25*5^n/9 -128*8^n/9 +25*10^n/2. - R. J. Mathar, Jun 20 2013

a(n) = 25*a(n-1)-216*a(n-2)+740*a(n-3)-800*a(n-4), with a(0)=1, a(1)=25, a(2)=409, a(3)=5565. - Harvey P. Dale, Aug 25 2014

Mathematica

CoefficientList[Series[1/((1-2x)(1-5x)(1-8x)(1-10x)), {x, 0, 20}], x] (* Harvey P. Dale, Aug 25 2014 *)
(* Alternative: *)
LinearRecurrence[{25, -216, 740, -800}, {1, 25, 409, 5565}, 20] (* Harvey P. Dale, Aug 25 2014 *)

Crossrefs

Sequence in context: A028044 A028057 A260953 * A024437 A028041 A025995

Adjacent sequences: A025995 A025996 A025997 * A025999 A026000 A026001

Keyword

nonn,easy,changed

Author

N. J. A. Sloane

Extensions

More terms from Michel Marcus, Jun 29 2026

Status

approved