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%I #17 Sep 18 2017 12:05:48
%S 1,2,3,4,5,6,7,8,9,10,11,18,13,14,15,16,17,18,19,50,21,22,23,54,25,26,
%T 27,98,29,30,31,32,33,34,35,36,37,38,39,250,41,42,43,242,75,46,47,162,
%U 49,50,51,338,53,54,55,686,57,58,59,150,61,62,147,64,65,66,67,578,69,70
%N Largest number with the prime signature of n using prime divisors of n.
%C Though a large number of initial terms match, this sequence is different from A069799. Example: a(1500) = a(2^2*3*5^3) = 5^3*3^2*2 = 2250, whereas A069799(1500) = 5^2*3*2^3 = 600.
%C The first term that is different from A069799 is a(18). - _Ivan Neretin_, Jul 29 2015
%H Reinhard Zumkeller, <a href="/A085079/b085079.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) >= n. - _Michel Marcus_, Jul 30 2015
%e 20 = 2^2*5, hence a(20) = 5^2*2 = 50.
%t Table[Times @@ ((ar = Transpose[FactorInteger[n]])[[1]]^Sort[ar[[2]]]), {n, 70}] (* _Ivan Neretin_, Jul 29 2015*)
%t fise[n_]:=Module[{fi=FactorInteger[n]},Times@@(fi[[All,1]]^Sort[ fi[ [All,2]]])]; Array[fise,100] (* _Harvey P. Dale_, Sep 18 2017 *)
%o (Haskell)
%o import Data.List (sort)
%o a085079 n = product $ zipWith (^) (a027748_row n) (sort $ a124010_row n)
%o -- _Reinhard Zumkeller_, Apr 27 2013
%Y Cf. A069799.
%Y Cf. A027748, A124010, A089247, A071364, A046523.
%K nonn
%O 1,2
%A _Amarnath Murthy_, Jul 01 2003
%E Corrected and extended by _Ray Chandler_, Aug 17 2003
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