cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A085079 Largest number with the prime signature of n using prime divisors of n.

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