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A089384 Greatest squarefree proper divisor of n, a(1) = 1. 1

%I

%S 1,1,1,2,1,3,1,2,3,5,1,6,1,7,5,2,1,6,1,10,7,11,1,6,5,13,3,14,1,15,1,2,

%T 11,17,7,6,1,19,13,10,1,21,1,22,15,23,1,6,7,10,17,26,1,6,11,14,19,29,

%U 1,30,1,31,21,2,13,33,1,34,23,35,1,6,1,37,15,38,11,39,1,10,3,41,1,42

%N Greatest squarefree proper divisor of n, a(1) = 1.

%H Amiram Eldar, <a href="/A089384/b089384.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = if n is squarefree then A032742(n) else A007947(n);

%F a(n) = A008966(n)*A032742(n) + (1-A008966(n))*A007947(n).

%t a[n_] := If[Max[(f = FactorInteger[n])[[;; , 2]]] == 1, n/f[[1, 1]], Times @@ (First@# & /@ f)]; Array[a, 84] (* _Amiram Eldar_, Aug 31 2019 *)

%Y Cf. A005117, A007947, A008966, A013929, A032742.

%K nonn

%O 1,4

%A _Reinhard Zumkeller_, Dec 28 2003

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Last modified September 29 07:08 EDT 2020. Contains 337425 sequences. (Running on oeis4.)