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a(1) = 0; for n > 1, a(n) = A000265(A289271(n)).
4

%I #6 Jan 02 2019 11:55:35

%S 0,1,1,1,1,3,1,1,1,5,1,3,1,9,5,1,1,17,1,3,9,33,1,17,1,65,1,5,1,7,1,1,

%T 33,129,3,9,1,257,65,5,1,11,1,17,9,513,1,129,1,1025,257,33,1,2049,17,

%U 3,513,4097,1,7,1,8193,5,1,33,19,1,65,1025,13,1,3,1,16385,2049,129,9,35,1,65,1,32769,1,11,129,65537,4097,5,1,21,17,257

%N a(1) = 0; for n > 1, a(n) = A000265(A289271(n)).

%H Antti Karttunen, <a href="/A322995/b322995.txt">Table of n, a(n) for n = 1..10000</a>

%F a(1) = 0; for n > 1, a(n) = A000265(A289271(n)).

%F For all n >= 1, A000120(a(n)) = A001221(n).

%o (PARI)

%o A000265(n) = (n/2^valuation(n, 2));

%o A289271(n) = { my(v=0,i=0,x=1); for(d=2,oo,if(n==1, return(v)); if(1==gcd(x,d)&&1==omega(d), if(!(n%d)&&1==gcd(d,n/d), v += 2^i; n /= d; x *= d); i++)); }; \\ After _Rémy Sigrist_'s program for A289271.

%o A322995(n) = if(1==n,0,A000265(A289271(n)));

%Y Cf. A000120, A001221, A000265, A289271.

%Y Cf. also A322993.

%K nonn

%O 1,6

%A _Antti Karttunen_, Jan 02 2019