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 A333730 #5 Apr 03 2020 21:53:07 %S A333730 0,0,0,1,1,4,14,130,1981,62616,2806508,158937367,10773254138, %T A333730 855658147832,78558952717569,8251166899386729,982806390786806618, %U A333730 131756175056777580011,19748565975966429686408,3289970442222058710279611,605948437043760750748781907,122796504004669690100342096563 %N A333730 Number of simple 4-regular bipartite graphs with 2n nodes. %F A333730 Euler transform of A006824. %Y A333730 Column k=4 of A008327. %K A333730 nonn %O A333730 1,6 %A A333730 _Andrew Howroyd_, Apr 03 2020