A022452 Expansion of 1/((1-x)*(1-5*x)*(1-7*x)*(1-8*x)).

1, 21, 290, 3330, 34491, 334791, 3109900, 27997860, 246301781, 2129087961, 18155626710, 153166509990, 1281087729871, 10640517267531, 87874475534720, 722286313011720, 5913514800094761, 48255642147081501

Offset

0,2

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (21,-151,411,-280).

Formula

a(n) = -1/168 +125*5^n/24 -343*7^n/12 +512*8^n/21. - R. J. Mathar, Mar 11 2011

a(n) = 15*a(n-1) - 56*a(n-2) + (5^(n+1) - 1)/4, a(0)=1, a(1)=21. - Vincenzo Librandi, Mar 12 2011

Mathematica

Table[-1/168 + 125*5^n/24 - 343*7^n/12 + 512*8^n/21, {n, 0, 50}] (* or *) LinearRecurrence[{21, -151, 411, -280}, {1, 21, 290, 3330}, 50] (* G. C. Greubel, Feb 28 2018 *)

Prog

(PARI) x='x+O('x^30); Vec(1/((1-x)*(1-5*x)*(1-7*x)*(1-8*x))) \\ G. C. Greubel, Feb 28 2018
(Magma) [-1/168 +125*5^n/24 -343*7^n/12 +512*8^n/21: n in [0..30]]; // G. C. Greubel, Feb 28 2018

Crossrefs

Sequence in context: A317042 A317696 A025967 * A183731 A101703 A102018

Adjacent sequences: A022449 A022450 A022451 * A022453 A022454 A022455

Keyword

nonn

Author

N. J. A. Sloane

Status

approved