term% cat index.txt FACTOR(1) General Commands Manual FACTOR(1)
NAME
factor, lfactor, qfactor, primes - factor a number, generate large
primes
SYNOPSIS
factor [ number ]
lfactor
qfactor
primes [ start [ finish ] ]
DESCRIPTION
Factor prints number and its prime factors, each repated the proper
number of times. The number must be positive and less than 2**56
(about 7.2e16)
If no number is given, factor reads a stream of numbers from the stan‐
dard input and factors them. It exits on any input not a positive in‐
teger.
Maximum time to factor is proportional to sqrt(n) and occurs when n is
prime or the square of a prime.
Lfactor reads one number from the standard input and factors it.
Worst-case running time is proportional to n**(1/5); it beats factor
for hard 12-digit problems and is workable to around n=10**30. Qfactor
reads one number from the standard input and factors it. It is almost
always better than lfactor , and will factor numbers up to about 40
digits.
Primes prints the prime numbers ranging from start to finish, where
start and finish are positive numbers less than 2**56. If finish is
missing, primes prints without end; if start is missing, it reads the
starting number from the standard input.
DIAGNOSTICS
`Ouch.' for input out of range or for garbage input.
BUGS
Lfactor makes mysterious progress reports on its arcane inner workings.
Qfactor does too.
FACTOR(1)