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 A180060 #17 Jun 27 2024 22:16:07
%S A180060 0,1,1,1,4,4,4,1,4,6,4,4,4,2,1,1,4,16,4,16,4,16,4,16,3,16,13,16,4,16,
%T A180060 4,1,25,16,29,16,4,16,22,16,4,16,4,20,32,16,4,16,22,16,1,16,4,52,8,32,
%U A180060 28,16,4,16,4,16,4,1,61,16,4,52,49,46,4,16,4,16,31,24,36,16,4,16
%N A180060 a(n) = 2^(2^n mod n) mod n.
%H A180060 Harvey P. Dale, <a href="/A180060/b180060.txt">Table of n, a(n) for n = 1..1000</a>
%F A180060 a(n) = 2^A015910(n) mod n.
%t A180060 Table[Mod[2^(Mod[2^n, n]), n], {n, 50}] (* _Alonso del Arte_, Jan 14 2011 *)
%t A180060 Table[PowerMod[2,PowerMod[2,n,n],n],{n,80}] (* _Harvey P. Dale_, Oct 09 2019 *)
%Y A180060 Cf. A000079, A179976.
%K A180060 nonn
%O A180060 1,5
%A A180060 _Juri-Stepan Gerasimov_, Jan 14 2011
%E A180060 Entries corrected by _R. J. Mathar_, Jan 14 2011