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 A184951 #19 May 01 2014 02:40:01 %S A184951 1,3,60,1,7848,1,3459383,7,2585136675,388,2807105250897,406824 %N A184951 Irregular triangle C(n,g) counting the connected 5-regular simple graphs on 2n vertices with girth at least g. %C A184951 The first column is for girth at least 3. The row length sequence starts: 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 4, 4. The row length is incremented to g-2 when 2n reaches A054760(5,g). %H A184951 Jason Kimberley, <a href="/wiki/User:Jason_Kimberley/C_k-reg_girth_ge_g_index">Index of sequences counting connected k-regular simple graphs with girth at least g</a> %e A184951 1; %e A184951 3; %e A184951 60, 1; %e A184951 7848, 1; %e A184951 3459383, 7; %e A184951 2585136675, 388; %e A184951 2807105250897, 406824; %Y A184951 Connected 5-regular simple graphs with girth at least g: this sequence (triangle); chosen g: A006821 (g=3), A058275 (g=4), A205295 (g=5). %Y A184951 Connected 5-regular simple graphs with girth exactly g: A184950 (triangle); chosen g: A184953 (g=3), A184954 (g=4), A184955 (g=5). %Y A184951 Triangular arrays C(n,g) counting connected simple k-regular graphs on n vertices with girth at least g: A185131 (k=3), A184941 (k=4), this sequence (k=5), A184961 (k=6), A184971 (k=7), A184981 (k=8). %K A184951 nonn,hard,more,tabf %O A184951 3,2 %A A184951 _Jason Kimberley_, Jan 10 2012 %E A184951 a(14) from _Jason Kimberley_, Dec 26 2012