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 A024021 #17 Jul 08 2025 17:26:35
%S A024021 1,1,-2044,-177139,-4194288,-48828093,-362796992,-1977326615,
%T A024021 -8589934336,-31381059097,-99999998976,-285311668563,-743008366592,
%U A024021 -1792160385845,-4049565153280,-8649755826607,-17592185978880
%N A024021 2^n-n^11.
%H A024021 Vincenzo Librandi, <a href="/A024021/b024021.txt">Table of n, a(n) for n = 0..235</a>
%H A024021 <a href="/index/Rec#order_13">Index entries for linear recurrences with constant coefficients</a>, signature (14,-90,352,-935,1782,-2508,2640,-2079,1210,-506,144,-25,2).
%F A024021 G.f.: -(3*x^12 +4059*x^11 +303304*x^10 +4254119*x^9 +17273235*x^8 +21709590*x^7 +3752904*x^6 -5331930*x^5 -1897719*x^4 -148785*x^3 -1968*x^2 -13*x +1) / ((x -1)^12*(2*x -1)). - _Colin Barker_, Oct 04 2014
%t A024021 Table[2^n-n^11,{n,0,20}] (* _Harvey P. Dale_, Aug 17 2019 *)
%o A024021 (Magma) [2^n-n^11: n in [0..30] ]; // _Vincenzo Librandi_, Apr 30 2011
%K A024021 sign,easy
%O A024021 0,3
%A A024021 _N. J. A. Sloane_