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 A115251 #4 Mar 30 2012 17:37:16 %S A115251 0,3,6,9,443,16,20,60,29,34,53,45,298,68,224,778,1356,4024,4186,8945, %T A115251 8463,20402,26125,86617,123486,133234,391349,365860,1290138,2973609, %U A115251 1454148,7623480,7988635,3080021 %N A115251 Least inverse of A114912, or -1 if no inverse exists. %C A115251 a(34) > 10^7. [From _Max Alekseyev_, Apr 28 2010] %K A115251 nonn,more %O A115251 0,2 %A A115251 _Christian G. Bower_, Jan 17 2006 %E A115251 a(21)-a(33) from _Max Alekseyev_, Apr 28 2010