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A364533
Number of strict integer partitions of n containing the sum of no pair of distinct parts. A variation of sum-free strict partitions.
17
1, 1, 1, 2, 2, 3, 3, 5, 5, 8, 7, 11, 11, 15, 15, 21, 22, 28, 32, 38, 40, 51, 55, 65, 74, 83, 94, 111, 119, 136, 160, 174, 196, 222, 252, 273, 315, 341, 391, 425, 477, 518, 602, 636, 719, 782, 886, 944, 1073, 1140, 1302, 1380, 1553, 1651, 1888, 1995, 2224, 2370
OFFSET
0,4
EXAMPLE
The a(1) = 1 through a(12) = 11 partitions (A..C = 10..12):
1 2 3 4 5 6 7 8 9 A B C
21 31 32 42 43 53 54 64 65 75
41 51 52 62 63 73 74 84
61 71 72 82 83 93
421 521 81 91 92 A2
432 631 A1 B1
531 721 542 543
621 632 732
641 741
731 831
821 921
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&Intersection[#, Total/@Subsets[#, {2}]] == {}&]], {n, 0, 30}]
CROSSREFS
For subsets of {1..n} we have A085489, complement A088809.
The non-strict version is A236912, complement A237113, ranked by A364461.
Allowing re-used parts gives A364346.
The non-binary version is A364349, non-strict A237667 (complement A237668).
The linear combination-free version is A364350.
The complement in strict partitions is A364670, w/ re-used parts A363226.
A000041 counts integer partitions, strict A000009.
A008284 counts partitions by length, strict A008289.
A108917 counts knapsack partitions, strict A275972.
A151897 counts sum-free subsets, complement A364534.
A323092 counts double-free partitions, ranks A320340.
Sequence in context: A244800 A275972 A364349 * A090492 A325768 A371736
KEYWORD
nonn
AUTHOR
Gus Wiseman, Aug 02 2023
STATUS
approved