factor, primes - factor a number, generate large primes
and its prime factors, each repeated the
proper number of times. The number must be positive and less than 2**54 (about
If no number
is given, factor
reads a stream of numbers from the
standard input and factors them. It exits on any input not a positive integer.
Maximum running time is proportional to sqrt(n).
prints the prime numbers ranging from start
, where start
are positive numbers less
than 2**56. If finish
is missing, primes
prints without end; if
is missing, it reads the starting number from the standard input.