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A326037 Heinz numbers of uniform perfect integer partitions. 3
1, 2, 4, 6, 8, 16, 32, 42, 64, 100, 128, 256, 512, 798, 1024, 2048, 2744, 4096, 8192, 16384, 32768, 42294, 52900, 65536 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
An integer partition of n is uniform if all parts appear with the same multiplicity, and perfect if every nonnegative integer up to n is the sum of a unique submultiset.
The enumeration of these partitions by sum is given by A089723.
LINKS
FORMULA
Intersection of A072774 (uniform), A299702 (knapsack), and A325781 (complete).
EXAMPLE
The sequence of all uniform perfect integer partitions together with their Heinz numbers begins:
1: ()
2: (1)
4: (11)
6: (21)
8: (111)
16: (1111)
32: (11111)
42: (421)
64: (111111)
100: (3311)
128: (1111111)
256: (11111111)
512: (111111111)
798: (8421)
1024: (1111111111)
2048: (11111111111)
2744: (444111)
4096: (111111111111)
8192: (1111111111111)
16384: (11111111111111)
MATHEMATICA
hwt[n_]:=Total[Cases[FactorInteger[n], {p_, k_}:>PrimePi[p]*k]];
Select[Range[1000], SameQ@@Last/@FactorInteger[#]&&Sort[hwt/@Divisors[#]]==Range[0, hwt[#]]&]
CROSSREFS
Sequence in context: A324579 A271520 A122408 * A100055 A334031 A304660
KEYWORD
nonn,more
AUTHOR
Gus Wiseman, Jun 04 2019
STATUS
approved

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Last modified April 25 05:18 EDT 2024. Contains 371964 sequences. (Running on oeis4.)