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%I #9 Oct 05 2018 05:39:40
%S 0,1,1,0,0,2,2,3,3,0,6,2,0,1,3,4,4,3,7,1,2,3,5,4,4,1,3,9,4,1,8,6,0,8,
%T 5,2,2,11,7,1,4,5,6,8,1,7,6,2,3,5,7,10,2,5,6,0,0,2,6,5,9,6,6,4,7,9,1,
%U 4,13,1,12,5,8,14,9,8,4,9,3,7,11,0,3,7,6
%N Let f(1) = 1, f(2) = 1 + i (where i denotes the imaginary unit), f(3) = 2 + i, and for n > 2, f(n+1) is the Gaussian integer in the first quadrant (with positive real part and nonnegative imaginary part) with least modulus and sharing at least one prime factor with f(n-1) but none with f(n) (in case of a tie, minimize the imaginary part); a(n) = the imaginary part of f(n).
%C See A319770 for the square of the modulus of f and additional comments.
%H Rémy Sigrist, <a href="/A319772/b319772.txt">Table of n, a(n) for n = 1..10000</a>
%Y Cf. A319770.
%K nonn
%O 1,6
%A _Rémy Sigrist_, Sep 27 2018