# Definition:Cyclotomic Ring

## Definition

Let $\Z \sqbrk {i \sqrt n}$ be the set $\set {a + i b \sqrt n: a, b \in \Z}$.

The algebraic structure $\struct {\Z \sqbrk {i \sqrt n}, +, \times}$ is the **$n$th cyclotomic ring**.

## Examples

### $5$th Cyclotomic Ring

The **$5$th cyclotomic ring** is the algebraic structure:

- $\struct {\Z \sqbrk {i \sqrt 5}, +, \times}$

where $\Z \sqbrk {i \sqrt 5}$ is the set $\set {a + i b \sqrt 5: a, b \in \Z}$.

$\struct {\Z \sqbrk {i \sqrt 5}, +, \times}$ is a ring.

## Also see

- Results about
**cyclotomic rings**can be found here.