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 A128239 #16 Jun 24 2023 13:41:58 %S A128239 0,0,0,1,2,9,28,107,376,1457,5733,24385,110240,540400,2867847 %N A128239 Number of n-node (unlabeled) graphs with girth 6. %o A128239 (nauty) geng -tfq $n | countg -qg6 --ng # _Martin Fuller_, May 03 2015 %Y A128239 Cf. A128041, A128042, A128236-A128243. %K A128239 nonn,more %O A128239 3,5 %A A128239 _Keith Briggs_, May 05 2007 %E A128239 Corrected and extended by _Martin Fuller_, May 01 2015