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A319163
Perfect powers whose prime multiplicities appear with relatively prime multiplicities.
7
4, 8, 9, 16, 25, 27, 32, 49, 64, 81, 121, 125, 128, 144, 169, 243, 256, 289, 324, 343, 361, 400, 512, 529, 576, 625, 729, 784, 841, 961, 1024, 1331, 1369, 1600, 1681, 1728, 1849, 1936, 2025, 2048, 2187, 2197, 2209, 2304, 2401, 2500, 2704, 2809, 2916, 3125
OFFSET
1,1
COMMENTS
Perfect powers n such that A181819(n) is not a perfect power (i.e. belongs to A007916).
EXAMPLE
The sequence of integer partitions whose Heinz numbers are in the sequence begins: (11), (111), (22), (1111), (33), (222), (11111), (44), (111111), (2222), (55), (333), (1111111), (221111), (66), (22222), (11111111), (77), (222211), (444), (88), (331111), (111111111), (99), (22111111), (3333), (222222), (441111).
MATHEMATICA
Select[Range[1000], And[GCD@@FactorInteger[#][[All, 2]]>1, GCD@@Length/@Split[Sort[FactorInteger[#][[All, 2]]]]==1]&]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 12 2018
STATUS
approved