OFFSET
1,4
EXAMPLE
The a(72) = 14 factorizations:
(2*2*2*3*3),
(2*2*2*9), (2*2*3*6),
(2*2*18), (2*3*12), (2*6*6), (3*3*8), (3*4*6),
(2*36), (3*24), (4*18), (6*12), (8*9),
(72).
MATHEMATICA
facs[n_]:=If[n<=1, {{}}, Join@@Table[Map[Prepend[#, d]&, Select[facs[n/d], Min@@#>=d&]], {d, Rest[Divisors[n]]}]];
stableQ[u_, Q_]:=!Apply[Or, Outer[#1=!=#2&&Q[#1, #2]&, u, u, 1], {0, 1}];
Table[Length[Select[facs[n], stableQ[Union[#], IntegerQ[Log[#1, #2]]&]&]], {n, 100}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Jan 04 2019
STATUS
approved