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%I #6 Jul 31 2013 13:36:35
%S 1,2,2,2,2,4,2,2,2,2,4,2,2,2,2,4,2,2,2,4,2,2,2,2,2,4,2,2,2,2,4,2,2,4,
%T 2,2,2,2,2,2,2,2,2,2,4,2,2,2,2,4,2,2,2,2,4,2,2,2,2,4,2,2,2,4,2,2,2,2,
%U 2,4,2,2,2,2,4,2,2,4,2,2,2,2,2,2,2,2,2,2,4,2,2,2,4
%N Stufe of Q(sqrt(-k)), where k is the n-th squarefree number.
%C A227782 is the main entry for this sequence.
%H Charles R Greathouse IV, <a href="/A227783/b227783.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A227782(A005117(n)).
%o (PARI) apply(n->if(n%8==7,4,if(n>1,2,1)),select(issquarefree, vector(200,i,i)))
%Y Cf. A227782, A227781.
%K nonn,easy
%O 1,2
%A _Charles R Greathouse IV_, Jul 31 2013