xref: /openbsd/games/factor/factor.6 (revision 17df1aa7)
1.\"	$OpenBSD: factor.6,v 1.11 2007/05/31 19:19:17 jmc Exp $
2.\"
3.\" Copyright (c) 1989, 1993
4.\"	The Regents of the University of California.  All rights reserved.
5.\"
6.\" This code is derived from software contributed to Berkeley by
7.\" Landon Curt Noll.
8.\"
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14.\" 2. Redistributions in binary form must reproduce the above copyright
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21.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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33.\"	@(#)factor.6	8.1 (Berkeley) 5/31/93
34.\"
35.\"
36.\" By: Landon Curt Noll   chongo@toad.com,   ...!{sun,tolsoft}!hoptoad!chongo
37.\"
38.\"   chongo <for a good prime call: 391581 * 2^216193 - 1> /\oo/\
39.\"
40.Dd $Mdocdate: May 31 2007 $
41.Dt FACTOR 6
42.Os
43.Sh NAME
44.Nm factor ,
45.Nm primes
46.Nd factor a number, generate primes
47.Sh SYNOPSIS
48.Nm factor
49.Op Ar number ...
50.Nm primes
51.Op Ar start Op Ar stop
52.Sh DESCRIPTION
53The
54.Nm
55utility will factor 64-bit positive integers.
56When a number is factored, it is printed, followed by a
57.Dq \: ,
58and the list of factors on a single line.
59Factors are listed in ascending order, and are preceded by a space.
60If a factor divides a value more than once, it will be printed
61more than once.
62.Pp
63When
64.Nm
65is invoked with one or more arguments,
66each argument will be factored.
67.Pp
68When
69.Nm
70is invoked with no arguments,
71.Nm
72reads numbers, one per line, from standard input, until end of file or error.
73White-space and empty lines are ignored.
74Numbers may be preceded by a single +.
75After a number is read, it is factored.
76Input lines must not be longer than 99 characters.
77.Pp
78The
79.Nm primes
80utility prints primes in ascending order, one per line, starting at or above
81.Ar start
82and continuing until, but not including
83.Ar stop .
84The
85.Ar start
86value must be at least 0 and not greater than
87.Ar stop .
88The
89.Ar stop
90value must not be greater than 4294967295.
91The default value of
92.Ar stop
93is 4294967295.
94.Pp
95When the
96.Nm primes
97utility is invoked with no arguments,
98.Ar start
99is read from standard input.
100.Ar stop
101is taken to be 4294967295.
102The
103.Ar start
104value may be preceded by a single +.
105The input line must not be longer than 99 characters.
106.Sh BUGS
107.Nm factor
108cannot handle the
109.Dq 10 most wanted
110factor list;
111.Nm primes
112won't get you a world record.
113