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%I #32 Feb 19 2024 01:52:40
%S 1,22,443,8864,177285,3545706,70914127,1418282548,28365650969,
%T 567313019390,11346260387811,226925207756232,4538504155124653,
%U 90770083102493074,1815401662049861495,36308033240997229916,726160664819944598337,14523213296398891966758
%N a(1)=1, a(n) = 20*a(n-1) + n.
%H Vincenzo Librandi, <a href="/A014904/b014904.txt">Table of n, a(n) for n = 1..200</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (22,-41,20). [_R. J. Mathar_, Jul 15 2010]
%F From _R. J. Mathar_, Jul 15 2010: (Start)
%F G.f.: x/((1-20*x)*(x-1)^2).
%F a(n) = 22*a(n-1) - 41*a(n-2) + 20*a(n-3). (End)
%t LinearRecurrence[{22, -41, 20}, {1, 22, 443}, 20] (* _Vincenzo Librandi_, Oct 20 2012 *)
%o (Magma) I:=[1, 22, 443]; [n le 3 select I[n] else 22*Self(n-1) - 41*Self(n-2) + 20*Self(n-3): n in [1..20]]; // _Vincenzo Librandi_, Oct 20 2012
%o (Maxima)
%o a[1]:1$
%o a[2]:22$
%o a[3]:443$
%o a[n]:=22*a[n-1]-41*a[n-2]+20*a[n-3]$
%o A014904(n):=a[n]$
%o makelist(A014904(n),n,1,30); /* _Martin Ettl_, Nov 06 2012 */
%K nonn
%O 1,2
%A _N. J. A. Sloane_, _Olivier Gérard_
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