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%I #9 Aug 26 2018 18:07:45
%S 0,1,1,1,1,3,1,0,1,3,1,3,1,3,3,0,1,3,1,3,3,3,1,2,1,3,0,3,1,7,1,0,3,3,
%T 3,3,1,3,3,2,1,7,1,3,3,3,1,2,1,3,3,3,1,2,3,2,3,3,1,7,1,3,3,0,3,7,1,3,
%U 3,7,1,3,1,3,3,3,3,7,1,2,0,3,1,7,3,3,3,2,1
%N Number of ways to write n as a product of a number that is not a perfect power and a squarefree number.
%H Andrew Howroyd, <a href="/A304326/b304326.txt">Table of n, a(n) for n = 1..10000</a>
%e The a(180) = 7 ways are (6*30), (12*15), (18*10), (30*6), (60*3), (90*2), (180*1).
%t radQ[n_]:=And[n>1,GCD@@FactorInteger[n][[All,2]]===1];
%t Table[Length[Select[Divisors[n],radQ[#]&&SquareFreeQ[n/#]&]],{n,100}]
%o (PARI) a(n)={sumdiv(n, d, d<>1 && !ispower(d) && issquarefree(n/d))} \\ _Andrew Howroyd_, Aug 26 2018
%Y Positions of zeros are A246549. Range appears to be A075427.
%Y Cf. A000961, A001055, A001597, A001694, A005117, A007916, A034444, A091050, A183096, A303386, A303707, A304327, A304328.
%K nonn
%O 1,6
%A _Gus Wiseman_, May 10 2018
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