Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #19 Jul 30 2015 17:11:14
%S 1,19,242,2618,26103,248997,2316784,21251956,193359485,1751044295,
%T 15814841406,142616378814,1284983809747,11572125768313,
%U 104185847231708,937857633325592,8441649467754489,75979521955403451
%N Expansion of 1/((1-x)(1-4x)(1-5x)(1-9x)).
%H Vincenzo Librandi, <a href="/A021772/b021772.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 (19, -119, 281, -180).
%F a(0)=1, a(1)=19, a(2)=242, a(3)=2618, a(n)=19*a(n-1)-119*a(n-2)+ 281*a(n-3)- 180*a(n-4). [_Harvey P. Dale_, Jul 23 2011]
%F a(n) = (3*9^(n+3)-30*5^(n+3)+32*4^(n+3)-5)/480. - _Yahia Kahloune_, May 23 2013.
%t CoefficientList[Series[1/((1-x)(1-4x)(1-5x)(1-9x)),{x,0,40}],x] (* or *) LinearRecurrence[{19,-119,281,-180},{1,19,242,2618},41] (* _Harvey P. Dale_, Jul 23 2011 *)
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_.