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 A090988 #11 Mar 28 2020 05:38:51
%S A090988 2,4,2,8,4,2,16,8,4,2,32,16,8,4,2,64,32,16,8,4,2,128,64,32,16,8,4,2,
%T A090988 256,128,64,32,16,8,4,2,512,256,128,64,32,16,8,4,2,1024,512,256,128,
%U A090988 64,32,16,8,4,2,2048,1024,512,256,128,64,32,16,8,4,2,4096,2048,1024,512,256
%N A090988 a(n) = 2^A004736(n).
%F A090988 a(n) = 2^A004736(n).
%e A090988 Triangle begins
%e A090988 2
%e A090988 4 2
%e A090988 8 4 2
%e A090988 16 8 4 2
%t A090988 Flatten[Table[2^n,{i,15},{n,i,1,-1}]] (* _Harvey P. Dale_, Dec 27 2011 *)
%Y A090988 Cf. A004736.
%K A090988 easy,nonn,tabl
%O A090988 1,1
%A A090988 _Alford Arnold_, Feb 29 2004