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%I #19 Jun 15 2020 16:33:18
%S 1,1,1,4,1,6,1,32,9,10,1,288,1,14,15,512,1,972,1,800,21,22,1,55296,25,
%T 26,243,1568,1,27000,1,16384,33,34,35,1679616,1,38,39,256000,1,74088,
%U 1,3872,6075,46,1,42467328,49,12500,51,5408,1,1417176,55,702464,57,58
%N Product of the nonprime divisors of n.
%H Michel Marcus, <a href="/A087652/b087652.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = 1 if n=1 or n is prime; a(n) = n if n=1 or n is semiprime (A001358).
%F From _Wesley Ivan Hurt_, Jun 08 2020: (Start)
%F a(n) = Product_{d|n, d nonprime} d.
%F If n is squarefree, then a(n) = n^(d(n)/2-1), where d(n) is the number of divisors of n (A000005). (End)
%F a(p^e) = p^((e^2+e-2)/2) for p prime, e > 0. - _Bernard Schott_, Jun 08 2020
%e n=12: nonprime divisors = {4,6,12}: a(12) = 4*6*12 = 288.
%o (PARI) a(n) = my(p=1); fordiv(n, d, if (!isprime(d), p*=d)); p; \\ _Michel Marcus_, Aug 05 2017
%Y Cf. A000005, A023890, A033273.
%K nonn
%O 1,4
%A _Reinhard Zumkeller_, Sep 25 2003
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