%I #11 Feb 05 2020 08:58:46
%S 2,3,2,5,3,7,2,3,5,11,3,13,7,7,5,17,3,19,5,7,11,23,3,5,13,13,7,29,7,
%T 31,5,11,17,17,7,37,19,19,13,41,7,43,11,11,23,47,5,7,7,17,17,53,13,13,
%U 11,19,29,59,7,61,31,31,7,13,13,67,17,23,23,71,7,73
%N a(n) is the greatest prime number of the form floor(n/k) where k > 0.
%H Rémy Sigrist, <a href="/A331959/b331959.txt">Table of n, a(n) for n = 2..10000</a>
%F a(n) = floor(n/A331954(n)).
%F a(p) = p for any prime number p.
%F a(2*p) = p for any prime number p.
%e For n = 8:
%e - floor(8/1) = 8 is not a prime number,
%e - floor(8/2) = 4 is not a prime number,
%e - floor(8/3) = 2 is a prime number,
%e - hence a(8) = 2.
%o (PARI) a(n) = for (k=1, oo, if (isprime(n\k), return (n\k)))
%Y Cf. A331954.
%K nonn
%O 2,1
%A _Rémy Sigrist_, Feb 02 2020
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