20D25 20E28 norm of Abelian non-cyclic subgroups norm of a group norm of decomposable subgroups decomposable group generalized norm of a group generalized norms generalized norms of groups locally finite group locally soluble groups non- Dedekindness non-Dedekind group non-periodic group norm of Abelian non-cyclic subgroups of a group norm of decomposable subgroups of a group norm of non-cyclic subgroups