%I A007668
%S A007668 1,2,6,12,840,332640
%N A007668 phi(n) divides sigma(n) and sigma(n)/n > sigma(m)/m for all m < n.
%H A007668 Walter Nissen, <a href="http://upforthecount.com">Home Page</a> (listed 
               in lieu of email address)
%Y A007668 Cf. A020492, A004394.
%Y A007668 Sequence in context: A058046 A074180 A126293 this_sequence A089415 A161324 
               A116534
%Y A007668 Adjacent sequences: A007665 A007666 A007667 this_sequence A007669 A007670 
               A007671
%K A007668 nonn
%O A007668 1,2
%A A007668 Walter Nissen