A-group
Definition
Symbol-free definition
A finite group is termed an A-group if every Sylow subgroup of it is Abelian.
Definition with symbols
A finite group <math>G</math> if for any <math>p</math>-Sylow subgroup <math>P</math> of <math>G</math>, <math>P</math> is an Abelian group.
Metaproperties
Direct product
A direct product of A-groups is an A-group. This is because the Sylow subgroups of the direct product are the direct products of the individual Sylow subgroups.
Subgroups
Any subgroup of an A-group is an A-group. This follows from the fact that a <math>p</math>-Sylow subgroup of a subgroup is a <math>p</math>-group in the whole group, and hence is contained in a <math>p</math>-Sylow subgroup of the whole group, which is Abelian. Hence, the <math>p</math>-Sylow subgroup of the subgroup is also Abelian.
Quotients
Any quotient of an A-group is an A-group. This follows from the fact that under a quotient mapping, the image of a Sylow subgroup remains a Sylow subgroup.