Group $U(n)$ closed under modular multiplication with every element is its own inverse
40131
If n is such that every element $(\mathbb{Z}/n\mathbb{Z})^{\times}$ is a root of $x^2-1$. Prove that $n$ divides 24.
139835
Every Finite Group is Isomorphic to a Subgroup of $A_n$
107687
How to prove that $U_{2^n}$ is isomorphic as group to $\mathbb Z_2 \times \mathbb Z_{2^{n-2}}$ for $n \ge 3$?
102971
Product of all elements of a finite group with an unique element of order 2
43759
Prove that the set $\mathrm{Aut}(G)$ of all automorphisms of the group $G$ with the operation of taking the composition is a group
131594
Can the symmetric group $S_n$ be imbedded as a subgroup in $A_{n+1}$?
130937
Embeddings of finite groups into $\mathrm{GL}_n(\mathbb{Z})$
149578
Subgroups of $(\mathbb Z_n,+)$
92193
Problem from Herstein on group theory
24561
$\mathbb S_n$ as semidirect product
47179
Prove that $[N, G']=1$ when $N$ is a nilpotent subgroup of a group $G$?
129827
Product of invertibles in $\Bbb Z_n$ [Wilson's Theorem generalization]
5906
All group homomorphism from $ \mathbb{Z} _m $ to $\mathbb{Z}_n $
98507
$\text{Aut}(F)$ is isomorphic to the multiplicative group of all $n\times n$ matrices over $\mathbb Z$
90332
Prove that that $U(n)$ is an abelian group.
120594
$\mathbb Z[i]/ \langle 1+2i \rangle \cong \mathbb Z_5$
122698
Construction of multiplicative group of complex numbers