Determine how many homomorphisms $f: \Bbb{Z}_4 \to \Bbb{Z}_{10}$ are there?
7938
Number of Homomorphisms from $\Bbb{Z}_m$ to $\Bbb{Z}_n$
93017
Isomorphism between $\Bbb R$ and $\Bbb R(X)$?
46971
Number of surjections from $\{1,...,m\}$ to $\{1,...,n\}$
137285
Prove $\mathbb{Z}_2 \times \mathbb{Z}_2$ is not isomorphic to $\mathbb{Z}_4$
64048
Describe all ring homomorphisms
90433
Isomorphisms between $(\mathbb Z_4,+)$ and $(U_5,*)$
64583
Number of surjective functions from A to B
159005
Finding all homomorphisms between two groups - couple of questions
97009
Image of ring homomorphism $\phi : \mathbb{Z}[t] \to \mathbb{Q}$?
40490
Birational isomorphism $\mathbb{P}^n\times \mathbb{P}^m\to \mathbb{P}^{n+m}$
105103
Automorphism from $\Bbb Q$ to $\Bbb Q$
27670
Group homomorphisms $\mathbb{Q}\to\mathbb{R}$
51334
Does there exist any surjective group homomorphism from $(\mathbb R^* , .)$ onto $(\mathbb Q^* , .)$?
108049
Determining the number of subgroups of $\Bbb Z_{14} \oplus \Bbb Z_{6}$
84658
What is the number of distinct subgroups of the automorphism group of $\mathbf{F}_{3^{100}}$?
121244
Homomorphisms and automorphisms on polynomial rings
131946
Order of an Element Under a Homomorphism