when $\Bbb{Z}^n$ isomorphic to $\Bbb{Z}^m$
79056
Prove that $\mathbb Z^n$ is not isomorphic to $\mathbb Z^m$ for $m\neq n$
64025
Ring homomorphisms from $\Bbb Q$ into a ring
26197
$B^n/S^{n-1}$ is homeomorphic to $S^n$
105103
Automorphism from $\Bbb Q$ to $\Bbb Q$
109596
Isomorphism from $\mathrm{Aut}(\mathbb{Z}/2\mathbb{Z}\times \mathbb{Z}/2\mathbb{Z})$ to $S_3$
84823
When is the group of units in $\mathbb{Z}_n$ cyclic?
154847
homomorphism from $S_3$ to $\mathbb Z/3\mathbb Z$
40321
$\operatorname{Aut}(\mathbb Z_n)$ is isomorphic to $U_n$.
98587
$\mathbb Z [X] / (X)$ isomorphic to $\mathbb Z[X] / (X+1)$ isomorphic to $\mathbb Z [X] / (X+2015)$
55900
Is there a ring homomorphism $M_2(\mathbb Z)\to \mathbb Z$?
146969
Proving that every group of order $4$ is isomorphic to $\Bbb Z_4$ or $\Bbb Z^*_8$
89415
Number of homomorphisms from $(\mathbb Q^+ , \,\cdot\,)$ to $(\mathbb Z_n , +)$
37351
Group of Order $p^2$ Isomorphic to $\mathbb{Z}_{p^2}$ or $\mathbb{Z}_{p}$ $\times$ $\mathbb{Z}_{p}$
40490
Birational isomorphism $\mathbb{P}^n\times \mathbb{P}^m\to \mathbb{P}^{n+m}$
59995
Isomorphism between $\mathbb{C}^* $ under multiplication with $\mathbb{C}$ under addition.
120035
Pattern in Isomorphisms between $\mathbb Z_m \times \mathbb Z_n$ and $\mathbb Z_{mn}$
52556
Isomorphism of $S^1$.