# Coprime Integers/Examples/7 and 27

## Example of Coprime Integers

$7$ and $27$ are coprime.

## Proof

The divisors of $7$ are $1$ and $7$.

The divisors of $27$ are $1$, $3$, $9$ and $27$.

The only integer in common between them is $1$.

Hence the result by definition of coprime.

$\blacksquare$

## Sources

- 1971: George E. Andrews:
*Number Theory*... (previous) ... (next): $\text {2-2}$ Divisibility: Example $\text {2-9}$