Groups whose proper subgroups have restricted infinite conjugacy classes

Abstract

A group G is said to have the AFC-property if for each element x of G at least one of the indices vertical bar G : C-G (x)vertical bar and vertical bar C-G (x) : x vertical bar is finite. The class of AFC-groups, which generalize FC-groups, has been studied by De Falco et al. (2017) and Shalev (1994). Here the structure of groups whose proper subgroups have the AFC-property is investigated.