%I
%S 6,15,18,21,30,33,35,42,44,45,48,51,54,60,66,69,70,78,84,87,90,99,102,
%T 105,114,119,120,123,126,132,133,135,138,140,141,144,147,150,153,159,
%U 162,165,168,174,177,180,186,195,198,204,207,210,213,217,220,221,222
%N Numbers n such that the denominator of sum(k=1,n,1/gcd(n,k)) is not equal to n.
%C Does lim n > infinity a(n)/n = 3 ?
%e sum(k=1,6,1/gcd(6,k))=7/2 hence 6 is in the sequence but sum(k=1,12,1/gcd(12,k))=77/12 so 12 is not in the sequence.
%o (PARI) for(n=1,300,if(denominator(sum(i=1,n,1/gcd(n,i)))<n,print1(n,",")))
%K easy,nonn
%O 1,1
%A _Benoit Cloitre_, May 18 2002
