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%I #19 Oct 17 2024 08:22:10
%S 1,1,1,2,2,2,2,3,3,3,3,3,3,3,3,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,8,8,8,
%T 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,13,13,13,
%U 13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13
%N Denominator of g(n) defined by g(1)=1, g(2n)=1/g(n)+1, g(2n+1)=g(2n).
%H Paolo Xausa, <a href="/A124230/b124230.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A000045(ceiling(log(n+1)/log(2))).
%F a(n) = A000045(A070939(n)). - _Paolo Xausa_, Oct 17 2024
%t Fibonacci[BitLength[Range[100]]] (* _Paolo Xausa_, Oct 16 2024 *)
%o (PARI) g(n)=if(n<2,1,if(n%2,g(n-1),1/g(n/2)+1))
%o a(n)=denominator(g(n))
%o (PARI) a(n)=fibonacci(ceil(log(n+1)/log(2)))
%Y Cf. A000045, A020650, A070939, A124229.
%K frac,nonn
%O 1,4
%A _Benoit Cloitre_, Oct 20 2006