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%I #17 Sep 08 2022 08:44:48
%S 1,28,521,8120,114765,1526196,19481953,241575376,2932083605,
%T 35012557580,412807072041,4818002535528,55771887460381,
%U 641245030592740,7331332058802545,83421584091633536,945410124787913253
%N Expansion of 1/((1-x)(1-6x)(1-10x)(1-11x)).
%H Vincenzo Librandi, <a href="/A024434/b024434.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (28,-263,896,-660).
%F a(n)=(18*11^(n+3) - 25*10^(n+3) + 9*6^(n+3) - 2)/900. [_Yahia Kahloune_, Jun 27 2013]
%F a(0)=1, a(1)=28, a(2)=521, a(3)=8120; for n>3, a(n) = 28*a(n-1) -263*a(n-2) +896*a(n-3)-660*a(n-4). - _Vincenzo Librandi_, Jul 16 2013
%t CoefficientList[Series[1 / ((1 - x) (1 - 6 x) (1 - 10 x) (1 - 11 x)), {x, 0, 20}], x] (* _Vincenzo Librandi_, Jul 16 2013 *)
%t LinearRecurrence[{28,-263,896,-660},{1,28,521,8120},20] (* _Harvey P. Dale_, Mar 31 2018 *)
%o (Magma) m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-x)*(1-6*x)*(1-10*x)*(1-11*x)))); /* or */ I:=[1,28,521,8120]; [n le 4 select I[n] else 28*Self(n-1)-263*Self(n-2)+896*Self(n-3)-660*Self(n-4): n in [1..25]]; // _Vincenzo Librandi_, Jul 16 2013
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_.