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 A243305 #7 Sep 08 2022 08:46:08
%S A243305 3,3,5,5,17,5,65,17,65,17,1025,17,4097,65,257,257,65537,65,262145,257,
%T A243305 4097,1025,4194305,257,1048577,4097,262145,4097,268435457,257,
%U A243305 1073741825,65537,1048577,65537,16777217,4097,68719476737,262145,16777217,65537,1099511627777
%N A243305 a(n) = 2^phi(n)+1 = A066781(n)+1.
%H A243305 Vincenzo Librandi, <a href="/A243305/b243305.txt">Table of n, a(n) for n = 1..1000</a>
%F A243305 a(n) = 2^A000010(n) + 1. - _Wesley Ivan Hurt_, Jun 04 2014
%p A243305 with(numtheory); A243305:=n->2^phi(n)+1; seq(A243305(n), n=1..50); # _Wesley Ivan Hurt_, Jun 04 2014
%t A243305 Table[2^EulerPhi[n] + 1, {n, 1, 50}]
%o A243305 (Magma) [2^EulerPhi(n)+1: n in [1..41]];
%Y A243305 Cf. A066781, A100371.
%K A243305 nonn
%O A243305 1,1
%A A243305 _Vincenzo Librandi_, Jun 04 2014