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Let f(n) be a sequence of distinct Gaussian integers such that f(1) = 0 and for any n > 1, f(n) = f(floor(n/2)) + k(n)*g((1+i)^(A000120(n)-1) * (1-i)^A023416(n)) where k(n) > 0 is as small as possible and g(z) = z/gcd(Re(z), Im(z)); a(n) is the imaginary part of f(n).
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%I #15 Jun 25 2019 12:01:20

%S 0,-1,1,-2,-1,1,2,-3,-3,-2,0,-1,2,3,3,-3,-4,-4,-3,-4,-2,0,1,-3,-1,2,3,

%T 3,4,4,3,-2,-4,-5,-5,-6,-5,-4,0,-5,-5,-3,1,-2,1,3,2,-6,-4,-3,2,-1,4,4,

%U 5,2,4,5,6,6,5,4,2,-1,-2,-4,-5,-5,-6,-7,-5,-6,-7

%N Let f(n) be a sequence of distinct Gaussian integers such that f(1) = 0 and for any n > 1, f(n) = f(floor(n/2)) + k(n)*g((1+i)^(A000120(n)-1) * (1-i)^A023416(n)) where k(n) > 0 is as small as possible and g(z) = z/gcd(Re(z), Im(z)); a(n) is the imaginary part of f(n).

%H Rémy Sigrist, <a href="/A326281/b326281.txt">Table of n, a(n) for n = 1..8191</a>

%H Rémy Sigrist, <a href="/A326281/a326281.png">Density plot of the first 2^22-1 terms</a>

%H Rémy Sigrist, <a href="/A326281/a326281.gp.txt">PARI program for A326281</a>

%o (PARI) See Links section.

%Y See A326280 for the real part of f and additional comment.

%Y Cf. A000120, A023416.

%K sign,look

%O 1,4

%A _Rémy Sigrist_, Jun 22 2019