A028170 Expansion of 1/((1-5x)(1-6x)(1-8x)(1-9x)).

1, 28, 495, 7070, 89201, 1038408, 11432275, 120872290, 1239829701, 12425000588, 122271240455, 1185943687110, 11369353359001, 107963322279568, 1017222704311035, 9522095291175530, 88651748959581101

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (28,-289,1302,-2160).

Formula

a(n) = 28*a(n-1) - 289*a(n-2) + 1302*a(n-3) - 2160*a(n-4). - Vincenzo Librandi, Feb 23 2012

a(n) = (9^(n+3) - 2*8^(n+3) + 2*6^(n+3) - 5^(n+3))/12. - Yahia Kahloune, Jun 03 2013

Mathematica

CoefficientList[Series[1/((1-5x)(1-6x)(1-8x)(1-9x)), {x, 0, 20}], x] (* Vincenzo Librandi, Feb 23 2012 *)

Prog

(Magma) I:=[1, 28, 495, 7070]; [n le 4 select I[n] else 28*Self(n-1)-289*Self(n-2)+1302*Self(n-3)-2160*Self(n-4): n in [1..40]]; // Vincenzo Librandi, Feb 23 2012

Crossrefs

Sequence in context: A263949 A240463 A140107 * A211677 A076172 A004336

Adjacent sequences: A028167 A028168 A028169 * A028171 A028172 A028173

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved