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 A253589 #5 Jan 13 2015 07:32:34 %S A253589 0,1,1,2,2,1,2,2,2,2,2,2,1,3,2,2,3,1,3,2,3,2,1,3,2,4,2,2,2,3,3,2,3,3, %T A253589 2,3,3,2,3,3,2,4,1,3,3,3,3,3,3,3,3,4,2,4,3,2,4,3,2,4,3,3,3,3,3,3,3,3, %U A253589 4,2,4,3,3,4,1,5,2,4,2,4,3,3,4,3,3,4 %N A253589 Binary weight of A252867(n). %C A253589 a(n) = A000120(A252867(n)). %H A253589 Reinhard Zumkeller, <a href="/A253589/b253589.txt">Table of n, a(n) for n = 0..10000</a> %e A253589 . n | A252867(n) | binary | a(n) %e A253589 . ----+------------+----------+-------- %e A253589 . 0 | 0 | 0 | 0 %e A253589 . 1 | 1 | 1 | 1 %e A253589 . 2 | 2 | 10 | 1 %e A253589 . 3 | 5 | 101 | 2 %e A253589 . 4 | 10 | 1010 | 2 %e A253589 . 5 | 4 | 100 | 1 %e A253589 . 6 | 3 | 11 | 2 %e A253589 . 7 | 12 | 1100 | 2 %e A253589 . 8 | 17 | 10001 | 2 %e A253589 . 9 | 6 | 110 | 2 %e A253589 . 10 | 9 | 1001 | 2 %e A253589 . 11 | 18 | 10010 | 2 %e A253589 . 12 | 8 | 1000 | 1 %e A253589 . 13 | 7 | 111 | 3 %e A253589 . 14 | 24 | 11000 | 2 %e A253589 . 15 | 33 | 100001 | 2 %e A253589 . 16 | 14 | 1110 | 3 %e A253589 . 17 | 32 | 100000 | 1 %e A253589 . 18 | 11 | 1011 | 3 %e A253589 . 19 | 36 | 100100 | 2 %e A253589 . 20 | 19 | 10011 | 3 %e A253589 . 21 | 40 | 101000 | 2 %e A253589 . 22 | 16 | 10000 | 1 %e A253589 . 23 | 13 | 1101 | 3 %e A253589 . 24 | 48 | 110000 | 2 %e A253589 . 25 | 15 | 1111 | 4 %e A253589 . 26 | 80 | 1010000 | 2 %e A253589 . 27 | 34 | 100010 | 2 %e A253589 . 28 | 20 | 10100 | 2 %e A253589 . 29 | 35 | 100011 | 3 %e A253589 . 30 | 28 | 11100 | 3 . %o A253589 (Haskell) %o A253589 a253589 = a000120 . a252867 %Y A253589 Cf. A252867, A000120, A007088. %K A253589 nonn %O A253589 0,4 %A A253589 _Reinhard Zumkeller_, Jan 12 2015