What is the ideal class group?
124107
Motivation behind the definition of ideal class group
31687
Classification of groups of order 30
156463
The complement of a proper subgroup generates the whole group
152904
Groups with Same Number Of Elements and Subgroups
97865
On Conjugacy Classes of Alternating Group $A_n$
95187
The set of homotopy classes
81406
Does every set have a group structure?
139702
Is $O_{C_p}$ and ${O_{C_p}}^\times$ a profinite group or compact?
47539
Find an abelian infinite group such that every proper subgroup is finite
63499
Groups of prime squared order
59727
Understanding equivalence class, equivalence relation, partition
149926
ZFC with class terms: is any set also a class?
118472
Is there a systematic way of finding the conjugacy class and/or centralizer of an element?
158368
Irrationals: A Group?
20877
The set of all nilpotent elements is an ideal
139218
Is this group solvable?
133378
Ideal class group of $\mathbb{Q} ( \sqrt{-23} ) $ is $\cong \mathbb{Z}/3$ by Minkowski bound.