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

%I #19 Aug 31 2018 19:24:21

%S 1,28,497,7148,90993,1070076,11908849,127304716,1320106865,

%T 13369686044,132894679281,1301200322604,12584262543217,

%U 120472024886332,1143539682545393,10777265023323212,100956186031265649

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

%H Harvey P. Dale, <a href="/A028145/b028145.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (28,-287,1268,-2016).

%F From _Vincenzo Librandi_, Mar 17 2011: (Start)

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

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

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

%t LinearRecurrence[{28,-287,1268,-2016},{1,28,497,7148},30] (* _Harvey P. Dale_, Oct 17 2011 *)

%o (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

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_