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%I #6 Jul 16 2019 06:15:46
%S 1,1,1,576,207360000,26956124946896309452800000000000,
%T 2841003716170671644367609186370356458508919205193278721884160000000000000000000000
%N Product of non-unitary divisors of n!.
%H Amiram Eldar, <a href="/A064031/b064031.txt">Table of n, a(n) for n = 1..10</a>
%F a(n) = A061538(n!) = (n!)^(A048105(n!)/2) = (n!)^((A000005(n!)-A034444(n!))/2)
%e n=6: 720 has 22 non-unitary divisors: a(6)=720^11=26956124946896309452800000000000
%t a[n_] := (n!)^(DivisorSigma[0, n!]/2 - 2^(PrimePi[n]-1)); Array[a, 10] (* _Amiram Eldar_, Jul 16 2019 *)
%Y Cf. A048656, A048657, A061537, A061538, A000142, A048105, A000005, A034444.
%K nonn
%O 1,4
%A _Labos Elemer_, Sep 13 2001
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