Any pattern for when the ring $\mathbb{Z}_m$ has units? ($m$ is any integer)
98232
What is a good way to introduce Euler's totient function?
55900
Is there a ring homomorphism $M_2(\mathbb Z)\to \mathbb Z$?
2884
$m,n>1$ are relatively prime integers , then are there at-least four idempotent (w.r.t. multiplication) elements in $\mathbb Z_{mn}$ ?
5223
$\mathbb{Z}_m \times \mathbb Z_n$ is cyclic if and only if $\gcd(m,n)=1$
136804
Computing $\mathrm{Hom}(\mathbb Z_n,\mathbb Z_m)$ as $\mathbb Z$-module
119052
Finding invertible elements in $\mathbb{Z}/m\mathbb{Z}$
1719
Ideals in the ring of Gaussian integers
124864
A not free $\mathbb{Z}$-module
35105
Density of ring of algebraic integers in $\mathbb C$
4353
Unit group of power series ring
154530
Rings whose elements are partitioned between units and zero-divisors.
32772
Proving units in a ring
19884
The units of $\mathbb Z_4[x]$
9794
Quotient ring of Gaussian integers $\mathbb{Z}[i]/(a+bi)$ when $a$ and $b$ are NOT coprime
104486
Ideal in $\mathbb Z[x]$ which is not two-generated
35691
$\mathbb Z[\sqrt 3]$ contains infinitely many units
33781
Is $\mathbb{Z}[x]/(x^2+1)$ isomorphic to $\mathbb{Z}[i]$?