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 A337220 #13 Sep 11 2020 04:07:44 %S A337220 2,1,1,1,1,3,5,1,27,41,19,565,1,7085,25,3,1266205,9,9099507,17602325, %T A337220 1,128207979,1657009,26494256091,172961,331,11147523830125, %U A337220 84179432287299,2405,145,297758653049289,9007199254741,1,281629680514649643,125400505,4246732448623781667,113 %N A337220 a(n) = (2^A195610(n) + 1)/A014657(n), for n >= 1. %Y A337220 Cf. A014657, A195610. %K A337220 nonn %O A337220 1,1 %A A337220 _Wolfdieter Lang_, Aug 22 2020