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 A015062 #4 Mar 30 2012 17:20:37
%S A015062 1,1,50,119757,14094337902,81246911474597002,
%T A015062 22950408766815313800875300,317662868501471575977731478166067621,
%U A015062 215446318838899436153587239312460946873230930006
%N A015062 q-Catalan numbers (binomial version) for q=-7.
%F A015062 {1 / (n+1)_q} {2 n choose n}_q.
%K A015062 nonn,easy
%O A015062 0,3
%A A015062 _Olivier Gérard_