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%I #15 May 12 2024 00:46:29
%S 1,36,21952,42998169600000000,30019840638976,
%T 8480691722056324948490652657647616,2343612817652433441167245312
%N Product of divisors of multiply-perfect numbers.
%C a(8) has 216 digits (116929951...000000000).
%C Supersequence of A067584.
%H Amiram Eldar, <a href="/A308423/b308423.txt">Table of n, a(n) for n = 1..11</a>
%F a(n) = A007955(A007691(n)).
%e For n = 3; a(3) = A007955(A007691(3)) = A007955(28) = 21952.
%t s = {}; Do[If[Divisible[DivisorSigma[1, n], n], AppendTo[s, n^(DivisorSigma[0, n]/2)]], {n, 10^4}]; s (* _Amiram Eldar_, Jul 04 2019 *)
%o (Magma) [&*[d: d in Divisors(m)]: m in [1..10^5] | IsIntegral(SumOfDivisors(m)/m)]
%Y Cf. A007691, A007955, A067584.
%Y See A088843 and A307741 for the number of and the sum of divisors of multiply-perfect numbers.
%K nonn,changed
%O 1,2
%A _Jaroslav Krizek_, May 26 2019
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