(Revised) Let $\phi : \Bbb Z \rightarrow \Bbb Z$ be given by $\phi(n) = 7n$. Find the image of $\phi$.
120971
(Revised) Prove that $\phi$ is a group homomorphism and find the kernel.
154841
Computing symmetry/combinatorial factor for a diagram in $\phi^4$ theory
106698
$\mathbb N$ when given the metric $d(m,n)=\frac{1}{m}-\frac{1}{n}$
30327
$\ker \phi = (x_1-a_1, ..., x_n-a_n)$ for a ring homomorphism $\phi: R[x_1, ..., x_n] \to R$
78342
When is $\phi(n)$ a prime number?
31216
Is the image of $\Phi_n(x) \in \mathbb{Z}[x]$ in $\mathbb{F}_q[x]$ still a cyclotomic polynomial?
144819
Proving $P(n) =n^{\phi(n)} \prod\limits_{d \mid n} \left(\frac{d!}{d^d} \right)^{\mu(n/d)}$
117681
For which Natural $n\ge2: \phi(n)=n/2$
85175
Continuous Images of $GL_n(\mathbb{R})$
138819
Prove that $\phi(n) \geq \sqrt{n}/2$
156195
1) Show that $(\Bbb Z[\sqrt2]^*, .)$ is infinite.
108691
Characterize the natural numbers $n$ such that there is a surjective group homomorphism from $S_n$ to $S_{n-1}$.
121880
How to show that $|D_{2n}| = 2n$ via the presentation?
114136
Euler's $\phi(n)$ function and solutions of $\phi(n) = 4294967296=2^{32}$
119118
Prove $n\mid \phi(2^n-1)$
9753
How to solve the equation $\phi(n) = k$?
33161
Find the image of (1,1,1) by T