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A286330
Number of partitions of n into a squarefree number of squarefree parts.
0
1, 1, 2, 3, 3, 5, 7, 10, 11, 15, 19, 26, 32, 42, 50, 66, 78, 101, 118, 150, 178, 224, 263, 327, 382, 471, 551, 670, 781, 944, 1098, 1317, 1526, 1821, 2105, 2498, 2879, 3399, 3908, 4592, 5266, 6164, 7056, 8220, 9388, 10897, 12424, 14368, 16342, 18843, 21394, 24585, 27858, 31932, 36119, 41277
OFFSET
0,3
EXAMPLE
a(8) = 11 because we have [7, 1], [6, 2], [6, 1, 1], [5, 3], [5, 2, 1], [3, 3, 2], [3, 2, 1, 1, 1], [3, 1, 1, 1, 1, 1], [2, 2, 2, 1, 1], [2, 2, 1, 1, 1, 1] and [2, 1, 1, 1, 1, 1, 1].
MATHEMATICA
Join[{1}, Table[Length[Select[IntegerPartitions[n], SquareFreeQ[Length[#]] && AllTrue[#, SquareFreeQ] &]], {n, 55}]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, May 07 2017
STATUS
approved