OFFSET
1,1
EXAMPLE
There are 6 factorizations of 60 with integer mean, namely:
(60)
(2*30)
(6*10)
(3*4*5)
(2*3*10)
(2*2*3*5)
so 60 is in the sequence.
MATHEMATICA
facs[n_]:=If[n<=1, {{}}, Join@@Table[Map[Prepend[#, d]&, Select[facs[n/d], Min@@#>=d&]], {d, Rest[Divisors[n]]}]];
Select[Range[100], Length[Select[facs[#], IntegerQ[Mean[#]]&]]>1&]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 30 2019
STATUS
approved