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 A026517 #23 Nov 28 2024 11:32:27 %S A026517 1,1,1,1,1,2,1,2,1,1,2,2,1,1,2,1,1,1,1,1,2,1,2,2,1,1,1,1,2,2,1,2,1,1, %T A026517 1,1,1,2,1,1,2,2,1,1,2,1,2,1,1,1,1,1,1,2,1,1,2,2,2,2,1,1,2,1,1,1,1,1, %U A026517 1,2,1,2,1,1,2,2,1,2,1,2,2,2,2,2,1,2,1,1,2,2 %N A026517 a(n) = t(5n), where t = A001285 (Thue-Morse sequence). %H A026517 Paolo Xausa, <a href="/A026517/b026517.txt">Table of n, a(n) for n = 0..10000</a> %H A026517 Michael Gilleland, <a href="/selfsimilar.html">Some Self-Similar Integer Sequences</a>. %t A026517 ThueMorse[Range[0, 500, 5]] + 1 (* _Paolo Xausa_, Nov 28 2024 *) %o A026517 (PARI) a(n)=1+hammingweight(5*n)%2 \\ _Charles R Greathouse IV_, May 09 2016 %Y A026517 Cf. A001285. %K A026517 nonn %O A026517 0,6 %A A026517 _Clark Kimberling_ %E A026517 Name and Pari code corrected by _Sean A. Irvine_, Oct 05 2019