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 A127802 #13 Jan 04 2025 23:16:18
%S A127802 1,3,0,3,0,0,0,3,0,0,0,0,0,0,0,3,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,3,0,0,
%T A127802 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,
%U A127802 0,0,0,0,0,0,0,0,0,0,0,0,0
%N A127802 a(0) = 1, a(n) = 3*A036987(n), n>1.
%C A127802 Row sums of number triangle A127801.
%H A127802 Antti Karttunen, <a href="/A127802/b127802.txt">Table of n, a(n) for n = 0..16384</a>
%t A127802 Join[{1},3*Rest[Table[PadRight[{1}, 2^k, 0], {k, 0, 6}]//Flatten]] (* _James C. McMahon_, Jan 04 2025 *)
%o A127802 (Python)
%o A127802 def A127802(n): return 3*int(not(n&(n+1))) if n else 1 # _Chai Wah Wu_, Jul 06 2022
%Y A127802 Cf. A036987, A043529.
%K A127802 nonn
%O A127802 0,2
%A A127802 _Paul Barry_, Jan 29 2007