Perform test whether a number is a prime using command-line `factor` utility.

Check the number `809`.

```\$ factor 809 | awk 'NF==2 { check="is a" } NF>2 { check="is not a" } { print \$1 " " check " prime number" }'
```
```809: is a prime number
```

Check the range of numbers between `30200` and `30225`.

```\$ factor \$(seq 30200 30225) | awk 'NF==2 { check="is a" } NF>2 { check="is not a" } { print \$1 " " check " prime number" }'
```
```30200: is not a prime number
30201: is not a prime number
30202: is not a prime number
30203: is a prime number
30204: is not a prime number
30205: is not a prime number
30206: is not a prime number
30207: is not a prime number
30208: is not a prime number
30209: is not a prime number
30210: is not a prime number
30211: is a prime number
30212: is not a prime number
30213: is not a prime number
30214: is not a prime number
30215: is not a prime number
30216: is not a prime number
30217: is not a prime number
30218: is not a prime number
30219: is not a prime number
30220: is not a prime number
30221: is not a prime number
30222: is not a prime number
30223: is a prime number
30224: is not a prime number
30225: is not a prime number
```

Display primes in the range of numbers between `100` and `120`.

```\$ factor \$(seq 100 120) | awk 'NF==2 { print substr(\$1, 1, length(\$1)-1) }'
```
```101
103
107
109
113
```

Display primes in the range of numbers between `1` and `10` using `for` loop.

```\$ for i in \$(seq 1 10); do factor \$i | awk 'NF==2 { print substr(\$1, 1, length(\$1)-1) }';  done
```

This is the slowest solution and susceptible to the situation in which you can exceed command length, so I suggest to use previous ones.