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a(n) = smallest number obtainable by permuting the exponents in the prime factorization of n.
6

%I #7 Sep 02 2015 13:58:34

%S 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,12,19,20,21,22,23,24,25,26,

%T 27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,

%U 20,51,52,53,24,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72

%N a(n) = smallest number obtainable by permuting the exponents in the prime factorization of n.

%H Reinhard Zumkeller, <a href="/A089247/b089247.txt">Table of n, a(n) for n = 1..10000</a>

%o (Haskell)

%o import Data.List (sort)

%o a089247 n = product $ zipWith (^)

%o (a027748_row n) (reverse $ sort $ a124010_row n)

%o -- _Reinhard Zumkeller_, Apr 27 2013

%o (PARI) a(n)=my(f=factor(n)); f[,2]=vecsort(f[,2],,4); factorback(f) \\ _Charles R Greathouse IV_, Sep 02 2015

%Y Cf. A027748, A124010, A046523, A071364, A085079.

%K easy,nonn

%O 1,2

%A _Sam Alexander_, Dec 11 2003