.th FACTOR VI 1/15/73 .sh NAME factor \*- discover prime factors of a number .sh SYNOPSIS .bd factor [ number ] .sh DESCRIPTION When .it factor is invoked without an argument, it waits for a number to be typed in. If you type in a positive number less than 2\u\s756\s0\d (about .if n 7.2e16) .if t 7.2\(mu10\u\s716\s0\d\|) 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. .s3 If .it factor is invoked with an argument, it factors the number as above and then exits. .s3 Maximum time to factor is proportional to .if n sqrt(n) .if t \(sr\o'\fIn\fR\(rn' and occurs when .it n is prime or the square of a prime. It takes 1 minute to factor a prime near 10\u\s713\s0\d. .sh DIAGNOSTICS `Ouch.' for input out of range or for garbage input. .sh BUGS