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%I #5 Jan 08 2020 09:45:01
%S 6,8,10,13,14,17,18,20,23,24,25,27,28,32,33,34,35,37,39,40,41,43,44,
%T 46,48,49,50,51,53,54,55,58,59,60,61,62,63,65,68,69,70,71,72,73,75,76,
%U 78,79,80,81,82,83,84,85,86,87,88,89,90,91,93,94,95,96,99
%N Numbers that are not the number of factorizations into factors > 1 of any positive integer.
%C Warning: I have only confirmed the first eight terms. The rest are derived from A045782. - _Gus Wiseman_, Jan 07 2020
%H R. E. Canfield, P. Erdős and C. Pomerance, <a href="http://math.dartmouth.edu/~carlp/PDF/paper39.pdf">On a Problem of Oppenheim concerning "Factorisatio Numerorum"</a>, J. Number Theory 17 (1983), 1-28.
%t nn=15;
%t fam[n_]:=fam[n]=If[n<=1,{{}},Join@@Table[Map[Prepend[#,d]&,Select[fam[n/d],Min@@#>=d&]],{d,Rest[Divisors[n]]}]];
%t nds=Length/@Array[fam[#]&,2^nn];
%t Complement[Range[nn],nds]
%Y Complement of A045782.
%Y The strict version is A330975.
%Y Factorizations are A001055, with image A045782.
%Y Strict factorizations are A045778, with image A045779.
%Y The least number with n factorizations is A330973(n).
%Y Cf. A033833, A045779, A045783, A317145, A330935, A330972, A330974, A330977, A330991.
%K nonn
%O 1,1
%A _Gus Wiseman_, Jan 07 2020
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