A294150 Number of knapsack partitions of n that are also knapsack factorizations.
1, 1, 1, 2, 2, 4, 4, 6, 8, 10, 12, 13, 20, 20, 29, 30, 41, 41, 56, 53, 81, 75
Offset: 1
Examples
The a(12) = 13 partitions are: (12), (10 2), (9 3), (8 4), (7 5), (6 6), (8 2 2), (7 3 2), (5 5 2), (5 4 3), (4 4 4), (3 3 3 3), (2 2 2 2 2 2).
Links
- R. Ehrenborg and M. Readdy, The Mobius function of partitions with restricted block sizes, Advances in Applied Mathematics, Volume 39, Issue 3, September 2007, Pages 283-292.
Programs
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Mathematica
nn=22; dubQ[y_]:=And[UnsameQ@@Times@@@Union[Rest@Subsets[y]],UnsameQ@@Plus@@@Union[Rest@Subsets[y]]]; Table[Length@Select[IntegerPartitions[n],dubQ],{n,nn}]
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