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A350943
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Heinz numbers of integer partitions of which the number of even conjugate parts is equal to the number of odd parts.
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21
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1, 3, 6, 7, 13, 14, 18, 19, 26, 27, 29, 36, 37, 38, 42, 43, 53, 54, 58, 61, 63, 70, 71, 74, 78, 79, 84, 86, 89, 101, 105, 106, 107, 113, 114, 117, 122, 126, 130, 131, 139, 140, 142, 151, 156, 158, 162, 163, 171, 173, 174, 178, 181, 190, 193, 195, 199, 202, 210
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OFFSET
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1,2
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COMMENTS
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The Heinz number of a partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and integer partitions.
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LINKS
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FORMULA
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EXAMPLE
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The terms together with their prime indices begin:
1: ()
3: (2)
6: (2,1)
7: (4)
13: (6)
14: (4,1)
18: (2,2,1)
19: (8)
26: (6,1)
27: (2,2,2)
29: (10)
36: (2,2,1,1)
37: (12)
38: (8,1)
42: (4,2,1)
For example, the partition (6,3,2) has conjugate (3,3,2,1,1,1) and 1 = 1 so 195 is in the sequence.
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MATHEMATICA
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primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
conj[y_]:=If[Length[y]==0, y, Table[Length[Select[y, #>=k&]], {k, 1, Max[y]}]];
Select[Range[100], Count[primeMS[#], _?OddQ]==Count[conj[primeMS[#]], _?EvenQ]&]
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CROSSREFS
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These partitions are counted by A277579.
These are the positions of 0's in A350942.
A122111 = conjugation using Heinz numbers.
A316524 = alternating sum of prime indices.
The following rank partitions:
A350848: # of even conj parts = # of odd conj parts, counted by A045931.
A350944: # of odd parts = # of odd conjugate parts, counted by A277103.
A350945: # of even parts = # of even conjugate parts, counted by A350948.
Cf. A000070, A000290, A027187, A027193, A103919, A236559, A344607, A344651, A345196, A350950, A350951.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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