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%I #6 Mar 30 2012 18:39:05
%S 1,1,1,1,1,1,3,3,1,2,1,1,1,3,1,3,1,1,5,1,1,1,1,1,3,3,1,1,1,5,5,1,1,1,
%T 2,1,1,3,1,5,1,3,1,1,3,3,3,3,1,1,1,1,1,3,3,1,1,1,1,3,5,3,1,1,1,3,3,1,
%U 1,1,5,1,3,1,1,1,3,1,3,1,3,1,1,1,5,1,1,1,1,3,1,1,1,1,1,1,2,5,3,1,5,3,1,1,1
%N Minimum value of abs(prime(n)-k*tau(k)) for k>0.
%F It seems that if n > 1 then sum(k=1, n, a(kn)) > n*Log(Log(n)).
%o (PARI) a(n)=vecmin(vector(prime(n),k,abs(prime(n)-k*numdiv(k))))
%K nonn
%O 1,7
%A _Benoit Cloitre_, Aug 17 2002