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%I #11 Oct 30 2019 19:56:10
%S 1,3,5,3,7,15,11,3,5,21,13,15,17,33,35,3,19,15,23,21,55,39,29,15,7,51,
%T 5,33,31,105,37,3,65,57,77,15,41,69,85,21,43,165,47,39,35,87,53,15,11,
%U 21,95,51,59,15,91,33,115,93,61,105,67,111,55,3,119,195,71,57,145,231
%N If n = Product (p_j^k_j) then a(n) = Product (nextprime(p_j)), where nextprime = A151800.
%C All terms are odd.
%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F If n = Product (p_j^k_j) then a(n) = Product (prime(pi(p_j) + 1)), where pi = A000720.
%F a(n) = A007947(A003961(n)).
%e a(12) = a(2^2 * 3) = a(prime(1)^2 * prime(2)) = prime(2) * prime(3) = 3 * 5 = 15.
%p a:= n-> mul(nextprime(i[1]), i=ifactors(n)[2]):
%p seq(a(n), n=1..100); # _Alois P. Heinz_, Oct 30 2019
%t a[1] = 1; a[n_] := Times @@ (NextPrime[#[[1]]] & /@ FactorInteger[n]); Table[a[n], {n, 1, 70}]
%o (PARI) a(n) = my(f=factor(n)); prod(k=1, #f~, nextprime(f[k,1]+1)); \\ _Michel Marcus_, Oct 30 2019
%Y Cf. A000720, A003961, A007947, A045965, A045967, A048250, A151800, A328878, A328879.
%K nonn,mult
%O 1,2
%A _Ilya Gutkovskiy_, Oct 30 2019