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A325862 Number of integer partitions of n such that every set of distinct parts has a different sum. 30
1, 1, 2, 3, 5, 7, 10, 14, 19, 26, 34, 46, 58, 77, 93, 122, 146, 188, 217, 282, 327, 410, 470, 596, 673, 848, 947, 1178, 1325, 1629, 1798, 2213, 2444, 2962, 3247, 3935, 4292, 5149, 5579, 6674, 7247, 8590, 9221, 10964, 11804, 13870, 14843, 17480, 18675, 21866 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
A knapsack partition (A108917, A299702) is an integer partition such that every submultiset has a different sum. The one non-knapsack partition counted under a(4) is (2,1,1).
LINKS
EXAMPLE
The a(1) = 1 through a(7) = 14 partitions:
(1) (2) (3) (4) (5) (6) (7)
(11) (21) (22) (32) (33) (43)
(111) (31) (41) (42) (52)
(211) (221) (51) (61)
(1111) (311) (222) (322)
(2111) (411) (331)
(11111) (2211) (421)
(3111) (511)
(21111) (2221)
(111111) (4111)
(22111)
(31111)
(211111)
(1111111)
The three non-knapsack partitions counted under a(6) are:
(2,2,1,1)
(3,1,1,1)
(2,1,1,1,1)
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], UnsameQ@@Plus@@@Subsets[Union[#]]&]], {n, 0, 20}]
CROSSREFS
Dominates A108917.
Sequence in context: A116480 A023026 A096778 * A280277 A102108 A105780
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 31 2019
STATUS
approved

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Last modified August 29 12:23 EDT 2024. Contains 375517 sequences. (Running on oeis4.)