login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Expansion of 1/((1-x)*(1-9*x)*(1-10*x)).
1

%I #23 Sep 04 2017 03:51:13

%S 1,20,291,3730,44681,513240,5730271,62683550,675263061,7188478660,

%T 75807419051,793377882570,8251512054241,85374719599280,

%U 879483587504631,9026463398652790,92349281698986221,942254646401987100,9591402928728995011,97433737469672066210

%N Expansion of 1/((1-x)*(1-9*x)*(1-10*x)).

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (20,-109,90).

%F a(n) = (8*10^(n+2) - 9^(n+3) + 1)/72. - _Bruno Berselli_, Mar 21 2011

%F a(n) = 19*a(n-1) - 90*a(n-2) + 1, n >= 2. - _Vincenzo Librandi_, Mar 21 2011

%t Table[(2^(n + 4)*5^(n + 1) - 9^(n + 2) + 1)/72, {n, 40}] (* or *) CoefficientList[Series[1/((1 - z) (1 - 9*z) (1 - 10*z)), {z, 0, 40}], z] (* _Vladimir Joseph Stephan Orlovsky_, Jul 21 2011 *)

%Y Cf. A016218, A016228.

%K nonn

%O 0,2

%A _N. J. A. Sloane_