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.\" By: Landon Curt Noll chongo@toad.com, ...!{sun,tolsoft}!hoptoad!chongo 32.\" 33.\" chongo <for a good prime call: 391581 * 2^216193 - 1> /\oo/\ 34.\" 35.Dd January 12, 2020 36.Dt FACTOR 6 37.Os 38.Sh NAME 39.Nm factor , primes 40.Nd factor a number, generate primes 41.Sh SYNOPSIS 42.Nm 43.Op Fl h 44.Op Ar number ... 45.Nm primes 46.Op Fl h 47.Op Ar start Op Ar stop 48.Sh DESCRIPTION 49The 50.Nm 51utility will factor positive integers. 52When a number is factored, it is printed, followed by a 53.Ql \&: , 54and the list of factors on a single line. 55Factors are listed in ascending order, and are preceded by a space. 56If a factor divides a value more than once, it will be printed more than once. 57.Pp 58When 59.Nm 60is invoked with one or more arguments, each argument will be factored. 61.Pp 62When 63.Nm 64is invoked with no arguments, 65.Nm 66reads numbers, one per line, from standard input until end of file or 0 67is entered or an error occurs. 68Leading white-space and empty lines are ignored. 69.Pp 70Numbers may be preceded by a single 71.Ql + . 72Numbers can be either decimal or hexadecimal strings where the longest 73leading substring is used. 74Numbers are terminated by a non-digit character (such as a newline). 75If the string contains only decimal digits, it is treated as a 76decimal representation for a number. 77A hexadecimal string can contain an optional 78.Em 0x 79or 80.Em 0X 81prefix. 82After a number is read, it is factored. 83.Pp 84The 85.Nm primes 86utility prints primes in ascending order, one per line, starting at or above 87.Ar start 88and continuing until, but not including 89.Ar stop . 90The 91.Ar start 92value must be at least 0 and not greater than 93.Ar stop . 94The 95.Ar stop 96value must not be greater than the maximum. 97The default and maximum value of 98.Ar stop 99is 18446744073709551615. 100.Pp 101When the 102.Nm primes 103utility is invoked with no arguments, 104.Ar start 105is read from standard input and 106.Ar stop 107is taken to be the maximum. 108The 109.Ar start 110value may be preceded by a single 111.Ql + . 112The 113.Ar start 114value is terminated by a non-digit character (such as a newline). 115.Sh DIAGNOSTICS 116.Bl -diag 117.It "negative numbers aren't permitted" 118.It "illegal numeric format" 119.It "start value must be less than stop value" 120.It "Result too large" 121.El 122.Sh BUGS 123.Nm 124cannot handle the 125.Dq "10 most wanted" 126factor list, 127.Nm primes 128will not get you a world record. 129