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The squarefree kernel of Product prime(e(i)), when n = Product prime(i)^e(i).
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%I #21 Oct 02 2023 20:53:06

%S 1,2,2,3,2,2,2,5,3,2,2,6,2,2,2,7,2,6,2,6,2,2,2,10,3,2,5,6,2,2,2,11,2,

%T 2,2,3,2,2,2,10,2,2,2,6,6,2,2,14,3,6,2,6,2,10,2,10,2,2,2,6,2,2,6,13,2,

%U 2,2,6,2,2,2,15,2,2,6,6,2,2,2,14,7,2,2,6,2,2,2,10,2,6,2,6,2,2,2,22,2,6

%N The squarefree kernel of Product prime(e(i)), when n = Product prime(i)^e(i).

%H Antti Karttunen, <a href="/A329601/b329601.txt">Table of n, a(n) for n = 1..20000</a>

%H Antti Karttunen, <a href="/A329601/a329601.txt">Data supplement: n, a(n) computed for n = 1..100000</a>

%H <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>

%F a(n) = A007947(A181819(n)).

%F a(n) = A181819(A328400(n)), A181821(a(n)) = A328400(n).

%F a(A108951(n)) = A329607(n).

%F a(n) = A019565(A297404(n)). - _Peter Munn_, Oct 02 2023

%o (PARI)

%o A007947(n) = factorback(factorint(n)[, 1]);

%o A181819(n) = {my(f=factor(n)); prod(k=1, #f~, prime(f[k, 2])); }; \\ From A181819

%o A329601(n) = A007947(A181819(n));

%Y Cf. A007947, A019565, A108951, A181819, A181821, A297404, A328400, A329607.

%K nonn

%O 1,2

%A _Antti Karttunen_, Nov 19 2019