20F50 20E15 20F19 locally finite group self-normalizing subgroup 17A32 17A60 20F16 20F18 20F22 Baer radical Frattini subalgebra Gruenberg radical Leibniz algebra Primary: 20E15; Secondary: 20E25 \(\mathrm{GNA}\)-subgroup abnormal subgroup ascendant subgroup bilinear form cyclic Leibniz algebra extraspecial Leibniz algebra finite dimensional Leibniz algebra finite rank left (right) center left (right) idealizer locally nilpotent residual lower (upper) central series nilpotent Leibniz algebra normal subgroup pronormal subgroup