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A327521
Number of factorizations of the n-th squarefree number A005117(n) into squarefree numbers > 1.
0
1, 1, 1, 1, 2, 1, 2, 1, 1, 2, 2, 1, 1, 2, 2, 1, 2, 1, 5, 1, 2, 2, 2, 1, 2, 2, 1, 5, 1, 2, 1, 2, 1, 2, 2, 2, 1, 1, 2, 2, 5, 1, 2, 5, 1, 1, 2, 2, 5, 1, 2, 1, 2, 2, 2, 1, 2, 2, 2, 2, 1, 1, 5, 1, 5, 2, 1, 1, 5, 2, 1, 5, 2, 2, 2, 2, 2, 1, 2, 5, 1, 2, 2, 1, 5, 1, 2
OFFSET
1,5
FORMULA
MATHEMATICA
nn=100;
facsusing[s_, n_]:=If[n<=1, {{}}, Join@@Table[Map[Prepend[#, d]&, Select[facsusing[Select[s, Divisible[n/d, #]&], n/d], Min@@#>=d&]], {d, Select[s, Divisible[n, #]&]}]];
y=Select[Range[nn], SquareFreeQ];
Table[Length[facsusing[Rest[y], n]], {n, y}]
CROSSREFS
See link for additional cross-references.
Sequence in context: A374033 A026517 A072047 * A282870 A106802 A269254
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 15 2019
STATUS
approved