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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