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 A184964 #23 May 01 2014 02:37:01
%S A184964 0,0,0,0,0,0,0,0,0,0,0,0,1,0,1,1,9,6,267,3727,483012,69823723,
%T A184964 14836130862
%N A184964 Number of connected 6-regular simple graphs on n vertices with girth exactly 4.
%C A184964 Other than at n=0, this sequence first differs from A058276 at n = A054760(6,5) = 40.
%H A184964 Jason Kimberley, <a href="/wiki/User:Jason_Kimberley/C_k-reg_girth_eq_g_index">Index of sequences counting connected k-regular simple graphs with girth exactly g</a>
%e A184964 a(0)=0 because even though the null graph (on zero vertices) is vacuously 6-regular and connected, since it is acyclic, it has infinite girth.
%e A184964 The a(12)=1 graph is the complete bipartite graph K_{6,6}.
%Y A184964 Connected k-regular simple graphs with girth exactly 4: A006924 (k=3), A184944 (k=4), A184954 (k=5), this sequence (k=6), A184974 (k=7).
%Y A184964 Connected 6-regular simple graphs with girth at least g: A006822 (g=3), A058276 (g=4).
%Y A184964 Connected 6-regular simple graphs with girth exactly g: A184963 (g=3), this sequence (g=4).
%K A184964 nonn,hard,more
%O A184964 0,17
%A A184964 _Jason Kimberley_, Feb 28 2011