摘要 : A subgroup H of a group G is contranormal if H-G = G. In finite groups, if there are no proper contranormal subgroups, then the group is nilpotent but this is not true in infinite groups as the well-known Heineken-Mohamed groups s... 展开 A subgroup H of a group G is contranormal if H-G = G. In finite groups, if there are no proper contranormal subgroups, then the group is nilpotent but this is not true in infinite groups as the well-known Heineken-Mohamed groups show. We call such groups without proper contranormal subgroups "contranormal-free." In this article, we prove various results concerning contranormal-free groups proving, for example that locally generalized radical contranormal-free groups which have finite section rank are hypercentral. 收起