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Integer quotient of the largest and the smallest prime factors of n, with a(1) = 1.
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%I #13 Oct 24 2024 06:39:12

%S 1,1,1,1,1,1,1,1,1,2,1,1,1,3,1,1,1,1,1,2,2,5,1,1,1,6,1,3,1,2,1,1,3,8,

%T 1,1,1,9,4,2,1,3,1,5,1,11,1,1,1,2,5,6,1,1,2,3,6,14,1,2,1,15,2,1,2,5,1,

%U 8,7,3,1,1,1,18,1,9,1,6,1,2,1,20,1,3,3,21,9,5,1,2,1,11,10,23,3,1,1,3,3,2,1

%N Integer quotient of the largest and the smallest prime factors of n, with a(1) = 1.

%H Antti Karttunen, <a href="/A069897/b069897.txt">Table of n, a(n) for n = 1..65537</a>

%F a(n) = floor(A006530(n)/A020639(n)).

%t a[n_] := Module[{p = FactorInteger[n][[;;, 1]]}, Floor[p[[-1]] / p[[1]]]]; Array[a, 100] (* _Amiram Eldar_, Oct 24 2024 *)

%o (PARI) A069897(n) = if(1==n,1, my(f = factor(n), lpf = f[1, 1], gpf = f[#f~, 1]); (gpf\lpf)); \\ _Antti Karttunen_, Sep 07 2018

%Y Cf. A006530, A020639, A046665, A120454.

%K nonn,easy,look

%O 1,10

%A _Labos Elemer_, Apr 10 2002

%E Term a(1) = 1 prepended by _Antti Karttunen_, Sep 07 2018