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 A173922 #14 Apr 04 2024 07:54:05
%S A173922 0,1,0,1,0,0,1,1,0,0,1,1,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,0,
%T A173922 0,0,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,
%U A173922 0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0
%N A173922 In the sequence of nonnegative integers substitute all n by 2^floor(n/4) occurrences of (n mod 2).
%F A173922 a(n) = A173920(n+4,4).
%F A173922 a(n) = A000035(A002265(A030101(n+4))).
%t A173922 Flatten[Table[ConstantArray[Mod[n, 2], 2^Floor[n/4]], {n, 0, 20}]] (* _Paolo Xausa_, Apr 03 2024 *)
%Y A173922 Cf. A001477, A079944, A173923, A200675.
%K A173922 nonn
%O A173922 0,1
%A A173922 _Reinhard Zumkeller_, Mar 04 2010
%E A173922 Sequence definition changed for clarity.