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A299729 Heinz numbers of non-knapsack partitions. 34
12, 24, 30, 36, 40, 48, 60, 63, 70, 72, 80, 84, 90, 96, 108, 112, 120, 126, 132, 140, 144, 150, 154, 156, 160, 165, 168, 180, 189, 192, 198, 200, 204, 210, 216, 220, 224, 228, 240, 252, 264, 270, 273, 276, 280, 286, 288, 300, 308, 312, 315, 320, 324, 325 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
An integer partition is non-knapsack if there exist two different submultisets with the same sum. The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
LINKS
EXAMPLE
12 is the Heinz number of (2,1,1) which is not knapsack because 2 = 1 + 1.
MATHEMATICA
primeMS[n_]:=If[n===1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
Select[Range[100], !UnsameQ@@Plus@@@Union[Rest@Subsets[primeMS[#]]]&]
CROSSREFS
Sequence in context: A334760 A098714 A334758 * A325777 A364532 A350056
KEYWORD
nonn
AUTHOR
Gus Wiseman, Feb 17 2018
STATUS
approved

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Last modified May 20 19:00 EDT 2024. Contains 372720 sequences. (Running on oeis4.)