FACTOR(6) BSD Games Manual FACTOR(6)NAME
factor, primes -- factor a number, generate primes
SYNOPSIS
factor [-h] [number ...]
primes [-h] [start [stop]]
DESCRIPTION
The factor utility will factor positive integers. When a number is factored, it is printed, followed by a ':', and the list of factors on a
single line. Factors are listed in ascending order, and are preceded by a space. If a factor divides a value more than once, it will be
printed more than once.
When factor is invoked with one or more arguments, each argument will be factored.
When factor is invoked with no arguments, factor reads numbers, one per line, from standard input, until end of file or error. Leading
white-space and empty lines are ignored. Numbers may be preceded by a single '+'. Numbers are terminated by a non-digit character (such as
a newline). After a number is read, it is factored.
The primes utility prints primes in ascending order, one per line, starting at or above start and continuing until, but not including stop.
The start value must be at least 0 and not greater than stop. The stop value must not be greater than the maximum. The default and maximum
value of stop is 3825123056546413050.
When the primes utility is invoked with no arguments, start is read from standard input and stop is taken to be the maximum. The start value
may be preceded by a single '+'. The start value is terminated by a non-digit character (such as a newline).
DIAGNOSTICS
negative numbers aren't permitted
illegal numeric format
start value must be less than stop value
Result too large
BUGS
factor cannot handle the ``10 most wanted'' factor list, primes will not get you a world record.
primes is unable to list primes between 3825123056546413050 and 18446744073709551615 since it relies on strong pseudoprime tests after siev-
ing, and nobody has proven how many strong pseudoprime tests are required to prove primality for integers larger than 3825123056546413050.
BSD October 10, 2002 BSD
Check Out this Related Man Page
factor(1) User Commands factor(1)NAME
factor - obtain the prime factors of a number
SYNOPSIS
factor [integer]
DESCRIPTION
factor writes to standard input all prime factors for any positive integer less than or equal to 10^14. The prime factors are written the
proper number of times.
If factor is used without an argument, it waits for an integer to be entered. After entry of the integer, it factors it, writes its prime
factors the proper number of times, and then waits for another integer. factor exits if a 0 or any non-numeric character is entered.
If factor is invoked with an argument (integer), it writes the integer, factors it and writes all the prime factors as described above, and
then exits. If the argument is 0 or non-numeric, factor writes a 0 and then exits.
The maximum time to factor an integer is proportional to sqrt(n), where n is the integer which is entered. factor will take this time when
n is prime or the square of a prime.
OPERANDS
integer Any positive integer less than or equal to 10^14.
EXIT STATUS
0 Successful completion.
1 An error occurred.
DIAGNOSTICS
factor prints the error message Ouch! for input out of range or for garbage input.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWesu |
+-----------------------------+-----------------------------+
SEE ALSO attributes(5)SunOS 5.11 31 Jan 1996 factor(1)
The called program gets as parameters two or more integers and
and returns 0 if all pairs of two are relatively primes, and 1
otherwise. The callee shall read a sequence of numbers and tell
whether they two by tworelatively primes. (1 Reply)
Hi,
Can anyone explain what is going on here:
michael-browns-powerbook-g4-15:~ msb65$ start=-1
michael-browns-powerbook-g4-15:~ msb65$ stop=1
michael-browns-powerbook-g4-15:~ msb65$ if ; then echo hello; fi
-bash: ; then echo hello; fi
hello
Are you not allowed to compare negative... (6 Replies)
Hello everyone !
Ive searched everywhere and still havnt found enough information to help me overcome (what seems like) a small problem
I have created a temporary file in which i store numbers which a seperated by a space, eg)
5 10 46
23 866 392
i wish to take the numbers for each line... (2 Replies)
Hello,
I have a command that I need to supply a negative number as a parameter; how do I do this? I have tried giving it with double quotes, "", but no avail.
Thanks,
Gussi (3 Replies)
Hi, I'm trying to check to see that the arguments given to my script are both numeric and positive integers. I'm using tcsh. I figured out the positive part, but I am having trouble with the arguments being numeric and integers
I have no idea where to get started with the checking them actually... (1 Reply)
Another question for you guys! This is so fun.
So I am playing around with the factor operation. I read in "man factor" that you can actually print a list of primes in between a range, using the syntax
factor ]
However, every time I enter two values, it just returns the factored value.... (1 Reply)
Hi Unix Gurus,
I have a requirement to generate positive random 16 and 13 digit numbers.
Here is the script I have so far.....
number=$RANDOM$RANDOM$RANDOM$RANDOM;
let "number %= 10000000000000";
echo $number
But sometimes it is generating negative numbers and also 15 digit... (8 Replies)
I'm trying to print out integers and space/newline for a nicer output, for example, every 20 integers in a row with ternary operator.
In C I could do it with:printf("%d%s",tmp_int, ((j+1)%20) ? "\t":"\n"); but could not figure out the equivalent in C++:
cout << ((j+1)%20)?... (4 Replies)