%I #11 Feb 24 2021 03:55:24
%S 1,1,1,1,1,2,1,1,1,1,1,2,1,1,3,1,1,1,2,2,3,1,1,1,1,3,1,2,1,1,1,2,1,1,
%T 2,1,1,3,2,4,2,1,1,1,1,1,1,1,4,2,2,1,1,1,1,1,1,1,1,2,3,2,1,4,3,1,2,1,
%U 1,9,2,1,1,1,1,2,1,1,1,1,1,2,1,2,5,1,3,3,1,2,1,2,2,1,1,8,1,1,1,6
%N lambda(y)/x, where y an odd squarefree semiprime and x = ord(2,y) the smallest positive integer such that 2^x == 1 mod y (the multiplicative order of 2 mod y).
%H Vassilis Papadimitriou, <a href="/A174435/b174435.txt">Table of n, a(n) for n=1,...,10000</a>.
%F Equals lambda(A046388)/ord(2, A046388), or lambda(A046388)/A174240.
%F a(n) = A002322(A046388(n))/A002326((A046388(n)+1)/2). - _Amiram Eldar_, Feb 24 2021
%e For n=1 the a(1)= 1, as the first odd squarefree semiprime is 15, lambda(15)=4 and ord(2,15)=4
%t (CarmichaelLambda[#]/MultiplicativeOrder[2, #]) & /@ Select[Range[1, 530, 2], PrimeOmega[#] == 2 && PrimeNu[#] == 2 &] (* _Amiram Eldar_, Feb 24 2021 *)
%Y Cf. A002322, A002326, A046388, A174240.
%K nonn
%O 1,6
%A _Vassilis Papadimitriou_, Mar 19 2010
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