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 A136043 #8 Jul 28 2025 10:54:32
%S A136043 1,1,1,1,2,1,1,1,3,2,5,1,6,1,1,1,4,3,9,2,2,5,4,1,10,6,9,1,14,1,1,1,5,
%T A136043 4,5,3,18,9,4,2,10,2,7,5,5,4,9,1,10,10,2,6,26,9,8,1,9,14,29,1,30,1,1,
%U A136043 1,6,5,33,4,11,5,14,3,3,18,9,9,15,4,17,2,27,10,41,2,2,7,11,5,4,5,4,4,3,9,14
%N A136043 Period-lengths of the base-2 MR-expansions of the reciprocals of the positive integers.
%C A136043 It appears that if p is a prime with 2 as a primitive root (A001122), then a(p)=(p-1)/2. This has been confirmed for primes up to 2000. See A136042 for the definition of the MR-expansion of a positive real number.
%F A136043 a(n) = 1 if n is a power of 2. It seems that otherwise a(n) = A119513(n). - _Andrei Zabolotskii_, Jul 28 2025
%e A136043 In A136042 it is shown that the base-2 MR-expansion of 1/5 is {3,1,3,1,3,1,3,1,...}, with period-length 2, so a(5)=2.
%Y A136043 Cf. A001122, A136042, A135044, A119513, A038553.
%K A136043 nonn
%O A136043 1,5
%A A136043 _John W. Layman_, Dec 12 2007