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 A220117 #10 Jan 10 2023 11:38:44 %S A220117 0,3,13,47,55,254,767,987,6909,16127,28657,28670,125951,196575,393213, %T A220117 4160255,4177911,25157623,25157631,46137325,67088375,268296191, %U A220117 268434303,268435455 %N A220117 First occurrence of n in A220115. %C A220117 Least k such that A000120(k) - A007895(k) = n. %Y A220117 Cf. A000120, A007895, A220115, A220118. %K A220117 nonn,base,more %O A220117 0,2 %A A220117 _Alex Ratushnyak_, Dec 05 2012