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A327907 Numbers with more than one factorization into at factors > 1 with integer mean.

%I A327907 #4 Oct 01 2019 09:50:08
%S A327907 4,8,9,12,15,16,20,21,24,25,27,28,32,33,35,36,39,40,42,44,45,48,49,50,
%T A327907 51,52,54,55,56,57,60,63,64,65,68,69,72,75,76,77,78,80,81,84,85,87,88,
%U A327907 91,92,93,95,96,99,100,104,105,108,110,111,112,114,115,116
%N A327907 Numbers with more than one factorization into at factors > 1 with integer mean.
%e A327907 There are 6 factorizations of 60 with integer mean, namely:
%e A327907   (60)
%e A327907   (2*30)
%e A327907   (6*10)
%e A327907   (3*4*5)
%e A327907   (2*3*10)
%e A327907   (2*2*3*5)
%e A327907 so 60 is in the sequence.
%t A327907 facs[n_]:=If[n<=1,{{}},Join@@Table[Map[Prepend[#,d]&,Select[facs[n/d],Min@@#>=d&]],{d,Rest[Divisors[n]]}]];
%t A327907 Select[Range[100],Length[Select[facs[#],IntegerQ[Mean[#]]&]]>1&]
%Y A327907 Complement of A327906.
%Y A327907 Positions of terms > 1 in A326622.
%Y A327907 Cf. A001055, A051293, A067538, A078175, A123528/A123529, A316413, A326515, A326516, A326666, A326667, A326671.
%K A327907 nonn
%O A327907 1,1
%A A327907 _Gus Wiseman_, Sep 30 2019