| Abstract: | Summary A T-group is a group in which normality is transitive, a T1-group is a group which is not a T-group but all of whose proper subgroups are T-groups, and a T2-group is a group which is not a T- group or a T1-group but all of whose proper subgroups are T-groups or T1-groups. In this note we determine all the finite T2-groups, and we show that all T2-groups which are either soluble or 2-groups are finite. We study also the groups in which every proper soluble subgroup is a T-group or a T1-group.
Lavoro eseguito nell'ambito del G.N.S.A.G.A. (C.N.R.). |
