1.\" Copyright (c) 1989, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Landon Curt Noll. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)factor.6 8.1 (Berkeley) 5/31/93 32.\" 33.\" $FreeBSD$ 34.\" 35.\" By: Landon Curt Noll chongo@toad.com, ...!{sun,tolsoft}!hoptoad!chongo 36.\" 37.\" chongo <for a good prime call: 391581 * 2^216193 - 1> /\oo/\ 38.\" 39.Dd January 12, 2020 40.Dt FACTOR 6 41.Os 42.Sh NAME 43.Nm factor , primes 44.Nd factor a number, generate primes 45.Sh SYNOPSIS 46.Nm 47.Op Fl h 48.Op Ar number ... 49.Nm primes 50.Op Fl h 51.Op Ar start Op Ar stop 52.Sh DESCRIPTION 53The 54.Nm 55utility will factor positive integers. 56When a number is factored, it is printed, followed by a 57.Ql \&: , 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 more than once. 61.Pp 62When 63.Nm 64is invoked with one or more arguments, each argument will be factored. 65.Pp 66When 67.Nm 68is invoked with no arguments, 69.Nm 70reads numbers, one per line, from standard input until end of file or 0 71is entered or an error occurs. 72Leading white-space and empty lines are ignored. 73.Pp 74Numbers may be preceded by a single 75.Ql + . 76Numbers can be either decimal or hexadecimal strings where the longest 77leading substring is used. 78Numbers are terminated by a non-digit character (such as a newline). 79If the string contains only decimal digits, it is treated as a 80decimal representation for a number. 81A hexadecimal string can contain an optional 82.Em 0x 83or 84.Em 0X 85prefix. 86After a number is read, it is factored. 87.Pp 88The 89.Nm primes 90utility prints primes in ascending order, one per line, starting at or above 91.Ar start 92and continuing until, but not including 93.Ar stop . 94The 95.Ar start 96value must be at least 0 and not greater than 97.Ar stop . 98The 99.Ar stop 100value must not be greater than the maximum. 101The default and maximum value of 102.Ar stop 103is 18446744073709551615. 104.Pp 105When the 106.Nm primes 107utility is invoked with no arguments, 108.Ar start 109is read from standard input and 110.Ar stop 111is taken to be the maximum. 112The 113.Ar start 114value may be preceded by a single 115.Ql + . 116The 117.Ar start 118value is terminated by a non-digit character (such as a newline). 119.Sh DIAGNOSTICS 120.Bl -diag 121.It "negative numbers aren't permitted" 122.It "illegal numeric format" 123.It "start value must be less than stop value" 124.It "Result too large" 125.El 126.Sh BUGS 127.Nm 128cannot handle the 129.Dq "10 most wanted" 130factor list, 131.Nm primes 132will not get you a world record. 133