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A319320
Number of integer partitions of n such that every distinct submultiset has a different LCM.
6
1, 1, 1, 1, 2, 1, 3, 2, 3, 4, 5, 4, 6, 7, 7, 9, 11, 12, 12, 15, 17, 20, 22, 24, 25, 31, 35, 39, 40, 48, 51, 55, 64, 73, 77, 85, 92, 104, 115, 126, 136, 147, 157, 176, 198, 211, 234, 246, 269, 294, 326, 350, 375, 403, 443, 475, 526, 560, 600, 650
OFFSET
1,5
COMMENTS
Note that such partitions are necessarily strict.
EXAMPLE
The a(19) = 12 partitions:
(19),
(10,9), (11,8), (12,7), (13,6), (14,5), (15,4), (16,3), (17,2),
(8,6,5), (11,5,3),
(7,5,4,3).
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&UnsameQ@@LCM@@@Union[Rest[Subsets[#]]]&]], {n, 30}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 17 2018
STATUS
approved