This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A129006 #24 Dec 28 2024 19:34:01
%S A129006 12,432,7776,103680,1166400,11757312,109734912,967458816,8162933760,
%T A129006 66512793600,526781325312,4074936532992,30901602041856,
%U A129006 230390642442240,1692665944473600,12277470317248512,88052482431516672
%N A129006 a(n) = (n^3 + n^2)*6^n.
%H A129006 Vincenzo Librandi, <a href="/A129006/b129006.txt">Table of n, a(n) for n = 1..1000</a>
%H A129006 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (24,-216,864,-1296).
%F A129006 G.f.: 12*x*(1+12*x)/(1-6*x)^4. - _Vincenzo Librandi_, Feb 12 2013
%F A129006 a(n) = 24*a(n-1)-216*a(n-2)+864*a(n-3)-1296*a(n-4). - _Vincenzo Librandi_, Feb 12 2013
%t A129006 CoefficientList[Series[12 (1 + 12 x)/(1 - 6 x)^4, {x, 0, 30}], x] (* _Vincenzo Librandi_, Feb 12 2013 *)
%t A129006 Table[(n^3+n^2)6^n,{n,20}] (* or *) LinearRecurrence[{24,-216,864,-1296},{12,432,7776,103680},20] (* _Harvey P. Dale_, Aug 16 2014 *)
%o A129006 (Magma) [(n^3+n^2)*6^n: n in [1..25]]; // _Vincenzo Librandi_, Feb 12 2013
%o A129006 (Magma) I:=[12,432,7776,103680]; [n le 4 select I[n] else 24*Self(n-1)-216*Self(n-2)+864*Self(n-3)-1296*Self(n-4): n in [1..25]]; // _Vincenzo Librandi_, Feb 12 2013
%Y A129006 Cf. A128796, A036289.
%K A129006 nonn,easy
%O A129006 1,1
%A A129006 _Mohammad K. Azarian_, May 01 2007