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 A304326 Number of ways to write n as a product of a number that is not a perfect power and a squarefree number. 11
 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, 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, 3, 7, 1, 3, 1, 3, 3, 3, 3, 7, 1, 2, 0, 3, 1, 7, 3, 3, 3, 2, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,6 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..10000 EXAMPLE The a(180) = 7 ways are (6*30), (12*15), (18*10), (30*6), (60*3), (90*2), (180*1). MATHEMATICA radQ[n_]:=And[n>1, GCD@@FactorInteger[n][[All, 2]]===1]; Table[Length[Select[Divisors[n], radQ[#]&&SquareFreeQ[n/#]&]], {n, 100}] PROG (PARI) a(n)={sumdiv(n, d, d<>1 && !ispower(d) && issquarefree(n/d))} \\ Andrew Howroyd, Aug 26 2018 CROSSREFS Positions of zeros are A246549. Range appears to be A075427. Cf. A000961, A001055, A001597, A001694, A005117, A007916, A034444, A091050, A183096, A303386, A303707, A304327, A304328. Sequence in context: A122779 A120323 A320476 * A099905 A268441 A264435 Adjacent sequences:  A304323 A304324 A304325 * A304327 A304328 A304329 KEYWORD nonn AUTHOR Gus Wiseman, May 10 2018 STATUS approved

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Last modified December 11 07:47 EST 2019. Contains 329914 sequences. (Running on oeis4.)