Prove there is no homomorphism from $Z_{16} \oplus Z_2 $ ont $Z_4 \oplus Z_4$
109987
No homomorphism from $Z_{16}\oplus Z_{2}$ onto $Z_{4}\oplus Z_{4}$.
85032
$Q(\mathbb{Z}[t]) / \mathbb{Z}[t]$ is not injective
57732
Rings of fractions and homomorphisms
25050
To prove that $(F,+)$ and $(F-\{0\},\cdot)$ are not isomorphic as groups.
78564
Prove: $D_{8n} \not\cong D_{4n} \times Z_2$.
125604
Proof that $\mathbb{Z}$ has no zero divisors
151786
Proving that there is no ideal $I$ in $\mathbb{Z}[t]$ such that $\mathbb{Z}[t]/I \cong \mathbb{Q}$
144105
Ring homomorphism from $\mathbb Z$ to $\mathbb Z$ is always identity or $0$
124140
Quick way to find the number of the group homomorphisms $\phi:{\bf Z}_3\to{\bf Z}_6$?
51695
Finding all homomorphisms between $\mathbb{Z}/m\mathbb{Z}$ and $\mathbb{Z}/n\mathbb{Z}$
92703
Proving that $\mathbb{Z}[x]$ and $\mathbb{Q}[x]$ are not isomorphic.
88645
Prove that the additive groups $\mathbb{R}$ and $\mathbb{Q}$ are not isomorphic.
143451
Homomorphism from $(\Bbb Q,+)$ to a finite group
79056
Prove that $\mathbb Z^n$ is not isomorphic to $\mathbb Z^m$ for $m\neq n$
13764
Homomorphisms from $\mathbb{Z} \rightarrow S_3$.
104562
Prove that $\mathbb{Z}$ is not isomorphic to additive group of any vector space over any field.
156549
Prove that there is no group $G$ s.t. $\operatorname{Aut}(G)=\mathbb{Q}$