**primes** prints the sequence of prime numbers:
2, 3, 5, 7, 11, and so on,
one per line.
If
*low* is supplied,
**primes** does not print any primes smaller than
*low*.

If
*high* is supplied,
**primes** does not print any primes larger than
*high*. If
*high* is not supplied,
**primes** stops at 1000000000;
the last prime is 999999937.

**primes** can handle
*high* as large as 1000000000000000.