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 A322075 Number of factorizations of n into nonprime squarefree numbers > 1. 1
 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,210 COMMENTS First term greater than 1 is a(210) = 4. LINKS G. C. Greubel, Table of n, a(n) for n = 1..10000 EXAMPLE The a(420) = 3 factorizations: (6*70), (10*42), (14*30). MATHEMATICA sqnopfacs[n_]:=If[n<=1, {{}}, Join@@Table[Map[Prepend[#, d]&, Select[sqnopfacs[n/d], Min@@#>=d&]], {d, Select[Rest[Divisors[n]], !PrimeQ[#]&&SquareFreeQ[#]&]}]] Table[Length[sqnopfacs[n]], {n, 100}] CROSSREFS Cf. A000469, A001055, A001221, A001222, A005117, A007716, A318871, A318953, A320655, A320656, A320658, A320659. Sequence in context: A079998 A339661 A320656 * A288220 A173856 A288926 Adjacent sequences:  A322072 A322073 A322074 * A322076 A322077 A322078 KEYWORD nonn AUTHOR Gus Wiseman, Nov 25 2018 STATUS approved

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Last modified July 25 03:53 EDT 2021. Contains 346283 sequences. (Running on oeis4.)