V4/usr/man/man6/factor.6

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.th FACTOR VI 1/15/73
.sh NAME
factor \*- discover prime factors of a number
.sh SYNOPSIS
.bd factor
.sh DESCRIPTION
When
.it factor
is invoked, it types
out `Enter:' at you.  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 repeat the number
back at you and then its prime factors each one printed
the proper number of times.  Then it says `Enter:' again.
To exit, feed it an EOT or a delete.
.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.
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