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A069897 Integer quotient of the largest and the smallest prime factors of n, with a(1) = 1.

%I A069897 #13 Oct 24 2024 06:39:12
%S A069897 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 A069897 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 A069897 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 A069897 Integer quotient of the largest and the smallest prime factors of n, with a(1) = 1.
%H A069897 Antti Karttunen, <a href="/A069897/b069897.txt">Table of n, a(n) for n = 1..65537</a>
%F A069897 a(n) = floor(A006530(n)/A020639(n)).
%t A069897 a[n_] := Module[{p = FactorInteger[n][[;;, 1]]}, Floor[p[[-1]] / p[[1]]]]; Array[a, 100] (* _Amiram Eldar_, Oct 24 2024 *)
%o A069897 (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 A069897 Cf. A006530, A020639, A046665, A120454.
%K A069897 nonn,easy,look
%O A069897 1,10
%A A069897 _Labos Elemer_, Apr 10 2002
%E A069897 Term a(1) = 1 prepended by _Antti Karttunen_, Sep 07 2018