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 A210715 #5 Dec 12 2012 11:28:15 %S A210715 0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,2,2,3,3,4,6,6,9,9,22,13,82,18,618,26, %T A210715 7164,36,107862,50,1876730,70,35924810,95,741405213,131,16356067216, %U A210715 323,383931367731,132977 %N A210715 Number of disconnected regular simple graphs on n vertices with girth exactly 5. %H A210715 Jason Kimberley, <a href="/wiki/User:Jason_Kimberley/D_k-reg_girth_eq_g_index">Index of sequences counting disconnected k-regular simple graphs with girth exactly g</a> %F A210715 a(n) = A185215(n) - A185216(n). %K A210715 nonn,more,hard %O A210715 0,16 %A A210715 _Jason Kimberley_, Dec 10 2012