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 A024026 #20 Sep 08 2022 08:44:48
%S A024026 1,2,1,0,17,118,513,1844,6049,18954,58049,175816,529713,1592126,
%T A024026 4780225,14345532,43042625,129135250,387414657,1162254608,3486776401,
%U A024026 10460343942,31381048961,94143166660,282429522657,847288593818
%N A024026 a(n) = 3^n - n^3.
%H A024026 Vincenzo Librandi, <a href="/A024026/b024026.txt">Table of n, a(n) for n = 0..200</a>
%F A024026 G.f.: (-1 + 5*x - 5*x^2 - 7*x^3 - 4*x^4)/((3*x-1)*(x-1)^4). - Maksym Voznyy (voznyy(AT)mail.ru), Aug 14 2009
%p A024026 seq(3^n-n^3, n=0..25); # _Zerinvary Lajos_, Jul 01 2007
%t A024026 lst={}; Do[AppendTo[lst,(3^n-n^3)],{n,0,5!}]; lst (* _Vladimir Joseph Stephan Orlovsky_, Jan 15 2009 *)
%o A024026 (Magma) [3^n-n^3: n in [0..30]]; // _Vincenzo Librandi_, May 14 2011
%o A024026 (PARI) a(n)=3^n-n^3 \\ _Charles R Greathouse IV_, Jul 02 2013
%K A024026 nonn,easy
%O A024026 0,2
%A A024026 _N. J. A. Sloane_