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 A064030 Product of unitary divisors of n!. 1
 1, 2, 36, 576, 207360000, 268738560000, 416336312719673760153600000000, 6984964247141514123629140377600000000, 300679807141675805997423113304381849600000000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Amiram Eldar, Table of n, a(n) for n = 1..17 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 Cf. A048656, A048657, A061537, A061538, A000142. Sequence in context: A025608 A230132 A141132 * A228790 A124104 A262973 Adjacent sequences: A064027 A064028 A064029 * A064031 A064032 A064033 KEYWORD nonn AUTHOR Labos Elemer, Sep 13 2001 STATUS approved

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Last modified December 4 18:39 EST 2023. Contains 367563 sequences. (Running on oeis4.)