|
| |
|
|
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
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,5
|
|
|
COMMENTS
|
Note that such partitions are necessarily strict.
|
|
|
LINKS
|
Table of n, a(n) for n=1..60.
|
|
|
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}]
|
|
|
CROSSREFS
|
Cf. A074761, A108917, A275972, A290103, A316313, A316429, A316431, A319315, A319318, A319327.
Sequence in context: A137661 A289152 A285779 * A305194 A303362 A183163
Adjacent sequences: A319317 A319318 A319319 * A319321 A319322 A319323
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
Gus Wiseman, Sep 17 2018
|
|
|
STATUS
|
approved
|
| |
|
|
