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A330216
Number of strict integer partitions of n whose product is a powerful number.
1
0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 3, 4, 3, 4, 5, 7, 8, 8, 10, 12, 12, 15, 18, 19, 20, 24, 25, 28, 38, 41, 43, 50, 55, 63, 79, 85, 88, 104, 116, 124, 143, 157, 173, 197, 214, 235, 274, 294, 319, 363, 393, 430, 487, 529, 577, 647, 692, 752, 856, 925, 992, 1099
OFFSET
0,10
EXAMPLE
The a(n) partitions for n = 4, 9, 12, 13, 16, 17, 18:
(4) (9) (8,4) (9,4) (16) (9,8) (12,6)
(8,1) (9,3) (6,4,3) (9,4,3) (16,1) (16,2)
(6,3,2,1) (8,4,1) (12,3,1) (8,6,3) (9,8,1)
(9,3,1) (9,4,2,1) (9,6,2) (8,6,3,1)
(6,4,3,2,1) (10,5,2) (9,4,3,2)
(12,3,2) (9,6,2,1)
(9,4,3,1) (10,5,2,1)
(12,3,2,1)
MATHEMATICA
powQ[n_]:=Min@@Last/@FactorInteger[n]>1;
Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&powQ[Times@@#]&]], {n, 0, 30}]
CROSSREFS
The non-strict version is A330106.
Powerful numbers are A001694.
Partitions whose product is a perfect power are A320322.
Sequence in context: A238957 A238970 A085755 * A241952 A236919 A138304
KEYWORD
nonn
AUTHOR
Gus Wiseman, Dec 05 2019
STATUS
approved