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.\" By: Landon Curt Noll chongo@toad.com, ...!{sun,tolsoft}!hoptoad!chongo 34.\" 35.\" chongo <for a good prime call: 391581 * 2^216193 - 1> /\oo/\ 36.\" 37.Dd January 12, 2020 38.Dt FACTOR 6 39.Os 40.Sh NAME 41.Nm factor , primes 42.Nd factor a number, generate primes 43.Sh SYNOPSIS 44.Nm 45.Op Fl h 46.Op Ar number ... 47.Nm primes 48.Op Fl h 49.Op Ar start Op Ar stop 50.Sh DESCRIPTION 51The 52.Nm 53utility will factor positive integers. 54When a number is factored, it is printed, followed by a 55.Ql \&: , 56and the list of factors on a single line. 57Factors are listed in ascending order, and are preceded by a space. 58If a factor divides a value more than once, it will be printed more than once. 59.Pp 60When 61.Nm 62is invoked with one or more arguments, each argument will be factored. 63.Pp 64When 65.Nm 66is invoked with no arguments, 67.Nm 68reads numbers, one per line, from standard input until end of file or 0 69is entered or an error occurs. 70Leading white-space and empty lines are ignored. 71.Pp 72Numbers may be preceded by a single 73.Ql + . 74Numbers can be either decimal or hexadecimal strings where the longest 75leading substring is used. 76Numbers are terminated by a non-digit character (such as a newline). 77If the string contains only decimal digits, it is treated as a 78decimal representation for a number. 79A hexadecimal string can contain an optional 80.Em 0x 81or 82.Em 0X 83prefix. 84After a number is read, it is factored. 85.Pp 86The 87.Nm primes 88utility prints primes in ascending order, one per line, starting at or above 89.Ar start 90and continuing until, but not including 91.Ar stop . 92The 93.Ar start 94value must be at least 0 and not greater than 95.Ar stop . 96The 97.Ar stop 98value must not be greater than the maximum. 99The default and maximum value of 100.Ar stop 101is 18446744073709551615. 102.Pp 103When the 104.Nm primes 105utility is invoked with no arguments, 106.Ar start 107is read from standard input and 108.Ar stop 109is taken to be the maximum. 110The 111.Ar start 112value may be preceded by a single 113.Ql + . 114The 115.Ar start 116value is terminated by a non-digit character (such as a newline). 117.Sh DIAGNOSTICS 118.Bl -diag 119.It "negative numbers aren't permitted" 120.It "illegal numeric format" 121.It "start value must be less than stop value" 122.It "Result too large" 123.El 124.Sh BUGS 125.Nm 126cannot handle the 127.Dq "10 most wanted" 128factor list, 129.Nm primes 130will not get you a world record. 131