20F19 20F18 3 20E15 2 20E34 2 20F16 2 20F22 2 abnormal subgroup 2 normal subgroup 2 pronormal subgroup 2 self-normalizing subgroup 2 (generalized) radical group 1 20E25 1 20E99 1 20F50 1 Abelian-by-nilpotent groups 1 Hirsh-Zaitsev rank 1 \(GNA\)-subgroup 1 \(G\)-eccentric subgroups 1 \(\mathrm{GNA}\)-subgroup 1 abnormal subgroups 1 arrangement of subgroups 1 contranormal subgroups 1 fan subgroups 1 hypercenter of a group 1 locally finite group 1 locally finite radical 1 locally nilpotent radical 1 locally nilpotent residual 1 pronormal subgroups 1 rank 1