%I #8 Mar 28 2017 14:50:32
%S 1,2,2,4,2,6,2,4,4,6,2,12,2,6,6,16,2,12,2,12,6,6,2,12,4,6,4,12,2,30,2,
%T 4,6,6,6,36,2,6,6,12,2,30,2,12,12,6,2,48,4,12,6,12,2,12,6,12,6,6,2,60,
%U 2,6,12,64,6,30,2,12,6,30,2,36,2,6,12,12,6,30
%N Smallest number with same factorization shape as n.
%C A284456 defines the factorization shape of a number.
%C A284456 corresponds to the fixed points of this sequence.
%H Rémy Sigrist, <a href="/A284476/b284476.txt">Table of n, a(n) for n = 1..10000</a>
%F To compute a(n):
%F 1) Factorize n: n = p_1^e_1 * ... * p_k^e_k,
%F 2) Compute a(e_i) for i=1..k,
%F 3) Sort the values computed at step 2 in descending order (keeping duplicates): you obtain, say, f_1 >= ... >= f_k,
%F 4) a(n) = Prod_{i=1..k} prime(i)^f_i.
%o (PARI) a(n) = my (f=factor(n)); \
%o my (x=vecsort(vector(#f~, i, a(f[i,2])),,4)); \
%o return (prod(i=1, #x, prime(i)^x[i]))
%Y Cf. A284456.
%K nonn
%O 1,2
%A _Rémy Sigrist_, Mar 27 2017
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