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A326016
Number of knapsack partitions of n such that no addition of one part up to the maximum is knapsack.
10
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 2, 0, 0, 1, 1, 0, 3, 0, 0, 0, 1, 0, 8, 0, 8, 4, 3, 0, 11, 5, 3, 2, 5, 0, 29, 2, 9, 8, 20, 2
OFFSET
1,21
COMMENTS
An integer partition is knapsack if every distinct submultiset has a different sum.
The Heinz numbers of these partitions are given by A326018.
EXAMPLE
The initial terms count the following partitions:
15: (5,4,3,3)
21: (7,6,5,3)
21: (7,5,3,3,3)
24: (8,7,6,3)
25: (7,5,5,4,4)
27: (9,8,7,3)
27: (9,7,6,5)
27: (8,7,3,3,3,3)
31: (10,8,6,6,1)
33: (11,9,7,3,3)
33: (11,8,5,5,4)
33: (11,7,6,6,3)
33: (11,7,3,3,3,3,3)
33: (11,5,5,4,4,4)
33: (10,9,8,3,3)
33: (10,8,6,6,3)
33: (10,8,3,3,3,3,3)
MATHEMATICA
sums[ptn_]:=sums[ptn]=If[Length[ptn]==1, ptn, Union@@(Join[sums[#], sums[#]+Total[ptn]-Total[#]]&/@Union[Table[Delete[ptn, i], {i, Length[ptn]}]])];
ksQ[y_]:=Length[sums[Sort[y]]]==Times@@(Length/@Split[Sort[y]]+1)-1;
maxks[n_]:=Select[IntegerPartitions[n], ksQ[#]&&Select[Table[Sort[Append[#, i]], {i, Range[Max@@#]}], ksQ]=={}&];
Table[Length[maxks[n]], {n, 30}]
KEYWORD
nonn,more
AUTHOR
Gus Wiseman, Jun 03 2019
STATUS
approved