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%I #15 Sep 08 2022 08:44:45
%S 1,26,457,6822,93333,1210938,15168529,185357774,2224062445,
%T 26316305730,307996949481,3573147901206,41156463852037,
%U 471239561238602,5368820120200513,60908872219620318,688516109116593309
%N Expansion of 1/((1-x)(1-4x)(1-10x)(1-11x)).
%H Vincenzo Librandi, <a href="/A021984/b021984.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (26,-219,634,-440).
%F a(n)=(27*11^(n+3) - 35*10^(n+3) + 15*4^(n+3) - 7)/1890. [_Yahia Kahloune_, Jun 29 2013]
%F a(0)=1, a(1)=26, a(2)=457, a(3)=6822; for n>3, a(n) = 26*a(n-1) -219*a(n-2) +634*a(n-3) -440*a(n-4). - _Vincenzo Librandi_, Jul 12 2013
%t CoefficientList[Series[1 / ((1 - x) (1 - 4 x) (1 - 10 x) (1 - 11 x)), {x, 0, 20}], x] (* _Vincenzo Librandi_, Jul 12 2013 *)
%t LinearRecurrence[{26,-219,634,-440},{1,26,457,6822},20] (* _Harvey P. Dale_, Jun 29 2018 *)
%o (Magma) I:=[1, 26, 457, 6822]; [n le 4 select I[n] else 26*Self(n-1)-219*Self(n-2)+634*Self(n-3)-440*Self(n-4): n in [1..25]]; /* or */ m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-x)*(1-4*x)*(1-10*x)*(1-11*x)))); // _Vincenzo Librandi_, Jul 12 2013
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_.
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