NAME
factor, primes - factor a number, generate large primes
SYNOPSIS
factor [ number ]
primes
DESCRIPTION
When factor is invoked without an argument, it waits for a number to be typed in. If you type in a positive number less than 256 (about 7.2e16) it will factor the number and print its prime factors; each one is printed the proper number of times. Then it waits for another number. It exits if it encounters a zero or any non-numeric character.
If factor is invoked with an argument, it factors the number as above and then exits.
Maximum time to factor is proportional to sqrt(n) and occurs when n is prime or the square of a prime. It takes 1 minute to factor a prime near 1014 on a PDP11.
When primes is invoked, it waits for a number to be typed in. If you type in a positive number less than 256 it will print all primes greater than or equal to this number.
DIAGNOSTICS
`Ouch.' for input out of range or for garbage input.