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%I #3 Mar 30 2012 18:50:55
%S 4,0,2,3,0,5,0,2,2,0,3,3,3,2,0,6,0,3,0,2,3,0,3,2,0,2,3,0,5,0,4,3,3,3,
%T 2,0,2,4,0,3,0,2,3,0,3,3,0,3,0,5,0,2,2,0,2,3,3,2,0,3,5,3,0,2,3,0,3,3,
%U 0,2,3,0,5,0,3,0,5,3,2,0,3,5,0,2,0,2,3,0,2,4,0,3,5,0,3,2,0,3,2,3,2,0,6,0,4
%N Number of times the n-th squarefree number occurs as maximal greatest common divisor of pairs of distinct squarefree numbers.
%C a(n) > 0 iff A005117(n) is an odd squarefree number: a(A100112(A056911(n)))>0;
%C a(n) = 0 iff A005117(n) is an even squarefree number: a(A100112(A039956(n)))=0.
%F a(n) = #{k: A123313(k) = A005117(n)}.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Sep 25 2006