Abstract.
A subgroup H of a group G is called a TI-subgroup if 
, for all 
, and
a group is called a CTI-group if all of its cyclic subgroups are TI-subgroups. In this paper, we determine the structure of non-nilpotent CTI-groups. Also we will show that if G is a nilpotent CTI-group, then G is either a Hamiltonian group or a non-abelian p-group.
Received: 2012-06-07
Revised: 2012-09-11
Published Online: 2013-03-01
Published in Print: 2013-03-01
© 2013 by Walter de Gruyter Berlin Boston
