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A316890
Heinz numbers of integer partitions into relatively prime parts whose reciprocal sum is 1.
2
2, 195, 3185, 6475, 10527, 16401, 20445, 20535, 21045, 25365, 46155, 164255, 171941, 218855, 228085, 267883, 312785, 333925, 333935, 335405, 343735, 355355, 414295, 442975, 474513, 527425, 549575, 607475, 633777, 691041, 711321, 722425, 753865, 804837, 822783
OFFSET
1,1
COMMENTS
The reciprocal sum of (y_1, ..., y_k) is 1/y_1 + ... + 1/y_k.
The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).
Includes 29888089, which is the first perfect power in the sequence and is absent from A316888.
MATHEMATICA
Select[Range[2, 100000], And[GCD@@PrimePi/@FactorInteger[#][[All, 1]]==1, Sum[m[[2]]/PrimePi[m[[1]]], {m, FactorInteger[#]}]==1]&]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Jul 16 2018
STATUS
approved