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 A320389 Product_i prime(i)^e(i), where e are the nonzero exponents in the prime factorization of n, sorted in increasing order. 1

%I

%S 1,2,2,4,2,6,2,8,4,6,2,18,2,6,6,16,2,18,2,18,6,6,2,54,4,6,8,18,2,30,2,

%T 32,6,6,6,36,2,6,6,54,2,30,2,18,18,6,2,162,4,18,6,18,2,54,6,54,6,6,2,

%U 150,2,6,18,64,6,30,2,18,6,30,2,108,2,6,18,18

%N Product_i prime(i)^e(i), where e are the nonzero exponents in the prime factorization of n, sorted in increasing order.

%C Here the exponents are sorted in increasing order; if they are sorted in decreasing order, we get A046523: the smallest number with the same prime signature as n.

%H Alois P. Heinz, <a href="/A320389/b320389.txt">Table of n, a(n) for n = 1..20000</a>

%p a:= n-> (l-> mul(ithprime(i)^l[i], i=1..nops(l)))(

%p sort(map(i-> i[2], ifactors(n)[2]))):

%p seq(a(n), n=1..100); # _Alois P. Heinz_, Feb 18 2020

%o (PARI) a(n)=factorback(matconcat([primes(#n=factor(n)[,2])~,vecsort(n)]))

%Y Cf. A046523.

%K nonn

%O 1,2

%A _M. F. Hasler_, Oct 12 2018

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Last modified September 19 07:24 EDT 2020. Contains 337178 sequences. (Running on oeis4.)