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 A185043 #20 Mar 17 2020 12:12:51 %S A185043 0,0,0,0,0,0,0,0,0,0,1,1,3,8,25,88,377,2026,13349,104593,930571, %T A185043 9124627,96699740,1095467916,13175254799,167460501260,2241576473025, %U A185043 31510509517563,464047467911837,7143984462730072,114749034352969037,1919656978492976231 %N A185043 Number of disconnected 4-regular simple graphs on n vertices with girth exactly 3. %H A185043 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 A185043 a(n) = A033483(n) - A185244(n). %Y A185043 4-regular simple graphs with girth exactly 3: A184943 (connected), this sequence (disconnected), A185143 (not necessarily connected). %Y A185043 Disconnected k-regular simple graphs with girth exactly 3: A210713 (any k), A210703 (triangle); for fixed k: A185033 (k=3), this sequence (k=4), A185053 (k=5), A185063 (k=6). %Y A185043 Disconnected 4-regular simple graphs with girth exactly g: this sequence (g=3), A185044 (g=4). %K A185043 nonn,hard %O A185043 0,13 %A A185043 _Jason Kimberley_, Feb 29 2012 %E A185043 Terms a(27)-a(31), due to the extension of A006820 by _Andrew Howroyd_, from _Jason Kimberley_, Mar 16 2020