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 A015077 #4 Mar 30 2012 17:20:37
%S A015077 1,1,82,537355,285611227174,12294441765937436842,
%T A015077 42868139471008987306371257332,
%U A015077 12107226510541735123474554479514562160539
%N A015077 q-Catalan numbers (binomial version) for q=-9.
%F A015077 {1 / (n+1)_q} {2 n choose n}_q.
%K A015077 nonn,easy
%O A015077 0,3
%A A015077 _Olivier Gérard_