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 A210713 #10 Jan 21 2013 08:45:01 %S A210713 0,0,0,0,0,0,1,1,2,2,5,4,16,13,64,98,597,2064,22472,112814,4799607, %T A210713 31138903,4207941575,115979716284,13482672620149 %N A210713 Number of disconnected regular simple graphs on n vertices with girth exactly 3. %H A210713 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 A210713 a(n) = A068932(n) - A185214(n). %Y A210713 This sequence is the row sum sequence of the triangle A210703. %Y A210713 Disconnected k-regular simple graphs with girth exactly 3: this sequence (any k), A210703 (triangle); for fixed k: A185033 (k=3), A185043 (k=4), A185053 (k=5), A185063 (k=6). %K A210713 nonn,more,hard %O A210713 0,9 %A A210713 _Jason Kimberley_, Apr 02 2012