# man(1) Manual page archive

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FACTOR(1)                                               FACTOR(1)

NAME
factor, qfactor, primes - factor a number, generate large
primes

SYNOPSIS
factor [ number ]

qfactor

primes [ start [ finish ] ]

DESCRIPTION
Factor prints number and its prime factors, each repeated
the proper number of times.  The number must be positive and
less than 2**56 (about 7.2e16)

If no number is given, factor reads a stream of numbers from
the standard input and factors them.  It exits on any input
not a positive integer.  Maximum running time is propor-
tional to sqrt(n).

Qfactor reads one number from the standard input and factors
it.  It will factor numbers up to about 40 digits.  For
large numbers it is much faster than factor.

Primes prints the prime numbers ranging from start to
finish, where start and finish are positive numbers less
than 2**56.  If finish is missing, primes prints without
end; if start is missing, it reads the starting number from
the standard input.

```