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A078599 Product of squarefree divisors of n.

%I A078599 #18 Dec 03 2023 14:52:36
%S A078599 1,2,3,2,5,36,7,2,3,100,11,36,13,196,225,2,17,36,19,100,441,484,23,36,
%T A078599 5,676,3,196,29,810000,31,2,1089,1156,1225,36,37,1444,1521,100,41,
%U A078599 3111696,43,484,225,2116,47,36,7,100,2601,676,53,36,3025,196,3249,3364
%N A078599 Product of squarefree divisors of n.
%H A078599 T. D. Noe, <a href="/A078599/b078599.txt">Table of n, a(n) for n = 1..1000</a>
%F A078599 a(n) = a(rad(n)), where rad(n) is the squarefree kernel of n.
%F A078599 a(A006881(n)) = A006881(n)^2.
%F A078599 a(A000040(n)) = A000040(n).
%F A078599 a(n) = A007955(A007947(n)). - _T. D. Noe_, Jul 08 2008
%F A078599 a(n) = A007947(n)^A007875(n). - _Amiram Eldar_, Sep 10 2020
%F A078599 a(n) = Product_{d|n} d^(mu(d)^2). - _Wesley Ivan Hurt_, Dec 03 2023
%e A078599 Divisors of n = 20: {1,2,4,5,10,20}, 4 = 2^2 and 20 = 5*2^2, therefore a(20) = 1*2*5*10 = 100.
%t A078599 Table[Times@@Select[Divisors[n],SquareFreeQ],{n,60}] (* _Harvey P. Dale_, Jul 03 2019 *)
%Y A078599 Cf. A000040, A005117, A006881, A007875, A007947, A007955, A034444.
%K A078599 nonn
%O A078599 1,2
%A A078599 _Reinhard Zumkeller_, Dec 09 2002