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A358102
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Numbers of the form prime(w)*prime(x)*prime(y) with w >= x >= y such that 2w = 3x + 4y.
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3
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66, 153, 266, 609, 806, 1295, 1599, 1634, 2107, 3021, 3055, 3422, 5254, 5369, 5795, 5829, 7138, 8769, 9443, 9581, 10585, 10706, 12337, 12513, 13298, 16465, 16511, 16849, 17013, 18602, 21983, 22145, 23241, 23542, 26159, 29014, 29607, 29945, 30943, 32623, 32809
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OFFSET
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1,1
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COMMENTS
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Also Heinz numbers of integer partitions (w,x,y) summing to n such that 2w = 3x + 4y, where the Heinz number of a partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
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LINKS
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EXAMPLE
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The terms together with their prime indices begin:
66: {1,2,5}
153: {2,2,7}
266: {1,4,8}
609: {2,4,10}
806: {1,6,11}
1295: {3,4,12}
1599: {2,6,13}
1634: {1,8,14}
2107: {4,4,14}
3021: {2,8,16}
3055: {3,6,15}
3422: {1,10,17}
5254: {1,12,20}
5369: {4,6,17}
5795: {3,8,18}
5829: {2,10,19}
7138: {1,14,23}
8769: {2,12,22}
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MATHEMATICA
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primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
Select[Range[1000], PrimeOmega[#]==3&&2*primeMS[#][[-1]]==3*primeMS[#][[-2]]+4*primeMS[#][[-3]]&]
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CROSSREFS
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These partitions are counted by A357849.
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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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