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 A153217 #5 Jan 27 2014 11:37:02
%S A153217 -1,-3,7,513,13983,357857,9546255,272475249,8375575711,277269756129,
%T A153217 9862141508151,375700268413577,15277275236695743,660913009555809345,
%U A153217 30322968902771794975,1471145239418922932193,75269422312346702251455
%N A153217 a(n)=n^(n+3)-(n+3)^n.
%t A153217 a[n_]:=n^(n+3)-(n+3)^n;lst={};Do[AppendTo[lst,a[n]],{n,0,4!}];lst
%t A153217 Table[n^(n+3)-(n+3)^n,{n,0,20}] (* _Harvey P. Dale_, Jan 27 2014 *)
%Y A153217 Cf. A046065
%K A153217 sign
%O A153217 0,2
%A A153217 _Vladimir Joseph Stephan Orlovsky_, Dec 20 2008
%E A153217 Minor edits from _Harry J. Smith_, Dec 23 2008