primes - generate prime numbers primes [ low [ high ] ] 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. primegen(3)