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A303365
Number of integer partitions of the n-th squarefree number using squarefree numbers.
4
1, 2, 3, 6, 9, 12, 28, 36, 60, 76, 96, 150, 228, 342, 416, 504, 877, 1484, 1759, 2079, 2885, 3387, 3968, 5413, 6304, 7328, 9852, 11395, 13159, 20082, 23056, 39532, 51385, 66488, 85660, 97078, 109907, 140465, 158573, 226918, 255268, 286920, 361606, 405470
OFFSET
1,2
FORMULA
a(n) = A073576(A005117(n)).
EXAMPLE
The a(5) = 9 partitions are (6), (51), (33), (321), (3111), (222), (2211), (21111), (111111).
MATHEMATICA
nn=80;
sqf=Select[Range[nn], SquareFreeQ];
ser=Product[1/(1-x^sqf[[n]]), {n, Length[sqf]}];
Table[SeriesCoefficient[ser, {x, 0, n}], {n, sqf}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Apr 22 2018
STATUS
approved