Every subgroup is a direct factor iff direct product of elementary Abelian groups
(Redirected from Every subgroup is a direct factor iff trivial or elementary Abelian)
Statement
The following are equivalent for a group:
- Every subgroup of the group is a direct factor.
- The group is either trivial or a direct product of elementary Abelian groups. In other words, it is a direct product of Abelian -groups for possibly different primes where each -group is an elementary Abelian group.
The implication (2) implies (1) requires the use of the axiom of choice.