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 A153059 #19 Feb 08 2017 02:10:00
%S A153059 0,-1,-1,-2,0,-5,19,354,125308,15702094855,246555782835417471015,
%T A153059 60789754049585540423053668337098365130214,
%U A153059 3695394197409101611007702673065886746062029284385286815035968423367078017175685784
%N A153059 a(0) = 0, a(n) = a(n-1)^2 - n.
%H A153059 Indranil Ghosh, <a href="/A153059/b153059.txt">Table of n, a(n) for n = 0..15</a>
%H A153059 <a href="/index/Aa#AHSL">Index entries for sequences of form a(n+1)=a(n)^2 + ...</a>
%F A153059 a(n) ~ c^(2^n), where c = 1.0469211647756727790926917384863725994592251990011465128982697545064576849... . - _Vaclav Kotesovec_, Dec 18 2014
%t A153059 a=0;lst={};Do[a=a^2-n;AppendTo[lst,a],{n,0,14}];lst
%t A153059 RecurrenceTable[{a[0]==0,a[n]==a[n-1]^2-n},a,{n,12}] (* _Harvey P. Dale_, Aug 05 2013 *)
%K A153059 sign,easy
%O A153059 0,4
%A A153059 _Vladimir Joseph Stephan Orlovsky_, Dec 17 2008