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 A168088 #20 Dec 15 2017 07:11:59
%S A168088 1,1,1,2,2,4,16,256,32768,536870912,72057594037927936,
%T A168088 324518553658426726783156020576256,
%U A168088 411376139330301510538742295639337626245683966408394965837152256
%N A168088 a(n) = 2^tetranacci(n).
%H A168088 Harvey P. Dale, <a href="/A168088/b168088.txt">Table of n, a(n) for n = 0..16</a>
%H A168088 <a href="/index/Di#divseq">Index to divisibility sequences</a>
%F A168088 a(n) = 2^A000078(n).
%t A168088 a={1,0,0,0};Flatten[Prepend[Table[s=Plus@@a;a=RotateLeft[a];z=a[[ -1]]=s;z=2^z,{n,12}],Table[0,{m,Length[a]-1}]]]
%t A168088 2^LinearRecurrence[{1,1,1,1},{0,0,0,1},15] (* _Harvey P. Dale_, Dec 12 2017 *)
%Y A168088 Cf. A000078.
%Y A168088 Subsequence of A000079.
%K A168088 nonn,easy
%O A168088 0,4
%A A168088 _Vladimir Joseph Stephan Orlovsky_, Nov 18 2009
%E A168088 a(0)-a(2) and offset corrected by _Charles R Greathouse IV_, Jul 19 2012