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 A232779 #12 Dec 25 2023 17:43:37 %S A232779 0,1,3,4,7,8,9,10,12,13,14,15,16,17,18,19,23,24,25,26,27,28,29,30,31, %T A232779 32,33,34,35,36,37,38,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55, %U A232779 56,57,58,59,60,61,62,63,64,65,66,67,68 %N A232779 Sum of iterated logs; a(n) = 0 if n = 0; otherwise n + a(floor(log_2(n))). %e A232779 a(5) = 5 + a(2) = 5 + 2 + a(1) = 5 + 2 + 1 + a(0) = 8. %Y A232779 Cf. A216761. %K A232779 nonn %O A232779 0,3 %A A232779 _Jeffrey Shallit_, Nov 30 2013