A089247 a(n) = smallest number obtainable by permuting the exponents in the prime factorization of n.

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, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 20, 51, 52, 53, 24, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72

Offset: 1

Author

Sam Alexander, Dec 11 2003

Keywords

• easy
• nonn

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

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

Programs

Haskell

import Data.List (sort)
a089247 n = product $ zipWith (^)
                      (a027748_row n) (reverse $ sort $ a124010_row n)
-- Reinhard Zumkeller, Apr 27 2013

PARI

a(n)=my(f=factor(n)); f[,2]=vecsort(f[,2],,4); factorback(f) \\ Charles R Greathouse IV, Sep 02 2015