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A318587
Heinz numbers of integer partitions whose sum of reciprocals squared is 1.
5
2, 81, 8775, 64827, 950625, 1953125, 7022925, 9055935, 21781575, 36020025, 50124555, 51883209, 57909033, 102984375, 118978125, 760816875, 816747435, 981059625, 1206902781, 1265058675, 1387132263, 2359670625, 3902169375, 4868424351, 5222768733, 5430160125
OFFSET
1,1
COMMENTS
The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).
EXAMPLE
The sequence of integer partitions with Heinz numbers in this sequence begins: (1), (2222), (633222), (4444222), (66333322).
MATHEMATICA
Select[Range[100000], Total[If[#==1, {}, Cases[FactorInteger[#], {p_, k_}:>k/PrimePi[p]^2]]]==1&]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Aug 29 2018
EXTENSIONS
a(6)-a(26) from Alois P. Heinz, Aug 30 2018
STATUS
approved