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 A061716 #18 Dec 13 2024 06:29:21
%S A061716 1,2,3,3,4,4,5,5,5,5,5,6,6,6,6,6,6,6,7,7,7,7,7,7,7,7,7,7,7,7,7,8,8,8,
%T A061716 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
%U A061716 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,10,10,10,10,10
%N A061716 Binary order of n-th prime.
%C A061716 Apart from the first terms, the same as A035100. - _R. J. Mathar_, Oct 02 2008
%H A061716 Harry J. Smith, <a href="/A061716/b061716.txt">Table of n, a(n) for n = 1..2000</a>
%F A061716 a(n) = ceiling(log_2(prime(n))) = A029837(A000040(n)).
%t A061716 Ceiling[Log2[Prime[Range[110]]]] (* _Harvey P. Dale_, Apr 12 2023 *)
%o A061716 (PARI) a(n) = { logint(prime(n)-1, 2) + 1 } \\ _Harry J. Smith_, Jul 26 2009
%Y A061716 Cf. A029837, A000040, A003070, A045716, A045716, A036378.
%K A061716 nonn
%O A061716 1,2
%A A061716 _Labos Elemer_, Jun 20 2001
%E A061716 Offset changed from 0 to 1 by _Harry J. Smith_, Jul 26 2009