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 A111417 #5 Sep 08 2013 13:30:49 %S A111417 0,0,1,0,0,0,3,0,0,0,0,0,10,0,0,0,0,0,0,0,35,0,0,0,0,0,0,0,0,0,126,0, %T A111417 0,0,0,0,0,0,0,0,0,0,462,0,0,0,0,0,0,0,0,0,0,0,0,0,1716,0,0,0,0,0,0,0, %U A111417 0,0,0,0,0,0,0,0,6435,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,24310,0 %N A111417 a(n) = A034869(n) - A008311(n). %F A111417 a(n) = A001700(m) if n = (m+1)*(m+2) and a(n) = 0 otherwise. %K A111417 easy,nonn %O A111417 0,7 %A A111417 _Philippe Deléham_, Nov 13 2005