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A064030
Product of unitary divisors of n!.
1
1, 2, 36, 576, 207360000, 268738560000, 416336312719673760153600000000, 6984964247141514123629140377600000000, 300679807141675805997423113304381849600000000
OFFSET
1,2
LINKS
FORMULA
a(n)=(n!)^(A034444(n!)/2)
EXAMPLE
n = 6 has 8 unitary divisors:{16,45,9,80,5,144,1,720}, a(6) = 720^4 = 268738560000
MATHEMATICA
a[n_] := (n!)^(2^(PrimePi[n]-1)); Array[a, 10] (* Amiram Eldar, Jul 16 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Sep 13 2001
STATUS
approved