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 A220118 #8 Jan 10 2023 11:38:50 %S A220118 0,4,32,320,520,512,12288,32768,131584,266240,1310720,8388608,4325376, %T A220118 39059456,100663296 %N A220118 First occurrence of -n in A220115. %C A220118 Least k such that A007895(k) - A000120(k) = n. %Y A220118 Cf. A000120, A007895, A220115, A220117. %K A220118 nonn,base,more %O A220118 0,2 %A A220118 _Alex Ratushnyak_, Dec 05 2012