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 A318721 Number of strict relatively prime factorizations of n. 10
 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 2, 0, 1, 0, 1, 0, 4, 0, 0, 1, 1, 1, 2, 0, 1, 1, 2, 0, 4, 0, 1, 1, 1, 0, 2, 0, 1, 1, 1, 0, 2, 1, 2, 1, 1, 0, 6, 0, 1, 1, 0, 1, 4, 0, 1, 1, 4, 0, 4, 0, 1, 1, 1, 1, 4, 0, 2, 0, 1, 0, 6, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,24 COMMENTS a(1) could be either 0 or 1. LINKS EXAMPLE The a(60) = 6 factorizations are (3*20), (4*15), (5*12), (2*3*10), (2*5*6), (3*4*5). MATHEMATICA strfacs[n_]:=If[n<=1, {{}}, Join@@Table[(Prepend[#1, d]&)/@Select[strfacs[n/d], Min@@#1>d&], {d, Rest[Divisors[n]]}]]; Table[Length[Select[strfacs[n], GCD@@#==1&]], {n, 50}] CROSSREFS Cf. A001055, A007716, A045778, A078374, A281116, A317748, A318720. Sequence in context: A323879 A129308 A159200 * A219201 A331838 A227836 Adjacent sequences:  A318718 A318719 A318720 * A318722 A318723 A318724 KEYWORD nonn AUTHOR Gus Wiseman, Sep 02 2018 STATUS approved

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Last modified June 5 12:47 EDT 2020. Contains 334840 sequences. (Running on oeis4.)