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%I #13 Jun 24 2018 19:38:02
%S 1,1,1,1,1,1,1,4,1,1,1,6,1,1,1,8,1,9,1,10,1,1,1,12,1,1,9,14,1,15,1,16,
%T 1,1,1,18,1,1,1,20,1,21,1,22,15,1,1,24,1,25,1,26,1,27,1,28,1,1,1,30,1,
%U 1,21,32,1,33,1,34,1,35,1,36,1,1,25,38,1,39,1,40,27,1,1,42,1,1,1,44,1
%N Largest nonprime proper divisor of n (with a(1)=1).
%C a(m)*a(n) <= a(m*n); a(m)*a(n) = a(m*n) iff m and n are prime or = 1. - _Reinhard Zumkeller_, Apr 11 2008
%H R. Zumkeller, <a href="/A063928/b063928.txt">Table of n, a(n) for n = 1..1000</a>
%o (PARI) { for (n=1, 1000, if (n==1, a=1, d=divisors(n); m=length(d); until (!isprime(a), m--; a=d[m])); write("b063928.txt", n, " ", a) ) } \\ _Harry J. Smith_, Sep 02 2009
%Y a(n)=1 if n is 1, prime (A000040), or the product of two primes (A001358), i.e., if n is in A037143, otherwise, with n in A033942, a(n)=A032742(n). Cf. A006530.
%K nonn
%O 1,8
%A _Henry Bottomley_, Aug 15 2001