A028145 Expansion of 1/((1-4x)(1-7x)(1-8x)(1-9x)).

1, 28, 497, 7148, 90993, 1070076, 11908849, 127304716, 1320106865, 13369686044, 132894679281, 1301200322604, 12584262543217, 120472024886332, 1143539682545393, 10777265023323212, 100956186031265649

Offset

0,2

Links

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (28,-287,1268,-2016).

Formula

From Vincenzo Librandi, Mar 17 2011: (Start)

a(n) = 28*a(n-1) - 287*a(n-2) + 1268*a(n-3) - 2016*a(n-4), n >= 4.

a(n) = 17*a(n-1) - 72*a(n-2) + (7^(n+1) - 4^(n+1)/3), n >= 2. (End)

a(n) = -2*8^(n+2) - 4^(n+2)/15 + 7^(n+3)/6 + 9^(n+3)/10. - R. J. Mathar, Mar 18 2011

Mathematica

LinearRecurrence[{28, -287, 1268, -2016}, {1, 28, 497, 7148}, 30] (* Harvey P. Dale, Oct 17 2011 *)

Prog

(PARI) Vec(1/((1-4*x)*(1-7*x)*(1-8*x)*(1-9*x))+O(x^99)) \\ Charles R Greathouse IV, Sep 27 2012

Crossrefs

Sequence in context: A046986 A330164 A323747 * A028167 A028136 A028090

Adjacent sequences: A028142 A028143 A028144 * A028146 A028147 A028148

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved