%I #13 Mar 05 2015 04:01:33
%S 66,210,282,364,510,642,930,966,1080,1092,1146,1624,2130,2226,2346,
%T 2586,2676,3560,3810,4278,4872,7965
%N Friendly numbers (see A074902) such that sigma(n) is not friendly.
%C I do not know how rigorously these numbers have been established. It is possible there are missing terms - see A074902. - _N. J. A. Sloane_, Sep 15 2002
%C From _Walter Nissen_, May 28 2011: (Start)
%C Yes; in particular, if perchance 10 should turn out to have a friend, then 10 would be a(0). Also 30 and 40 might possibly be in this sequence.
%C Numbers without friends are called solitary.
%C (End)
%e 6 is friendly, but so is sigma(6)=12, so 6 is not in the sequence. 210 is friendly (with 17360 for example), but sigma(210)=576 is not friendly.
%K nonn
%O 0,1
%A _Jon Perry_, Sep 12 2002