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A318719
Heinz numbers of strict integer partitions in which no two parts are relatively prime.
16
1, 2, 3, 5, 7, 11, 13, 17, 19, 21, 23, 29, 31, 37, 39, 41, 43, 47, 53, 57, 59, 61, 65, 67, 71, 73, 79, 83, 87, 89, 91, 97, 101, 103, 107, 109, 111, 113, 115, 127, 129, 131, 133, 137, 139, 149, 151, 157, 159, 163, 167, 173, 179, 181, 183, 185, 191, 193, 197
OFFSET
1,2
COMMENTS
The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).
MATHEMATICA
Select[Range[200], And[SquareFreeQ[#], And@@(GCD[##]>1&)@@@Select[Tuples[PrimePi/@FactorInteger[#][[All, 1]], 2], Less@@#&]]&]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 02 2018
STATUS
approved