`random'
--------

random([SEED])

SEED
RETURN
     non-negative integer

   * Generates a random number which is a non-negative integer less
     than 2^32.

   * If a non zero argument is specified, then after setting it as a
     random seed, a random number is generated.

   * As the default seed is fixed, the sequence of the random numbers is
     always the same if a seed is not set.

   * The algorithm is Mersenne Twister
     (http://www.math.keio.ac.jp/matsumoto/mt.html) by M. Matsumoto and
     T. Nishimura. The implementation is done also by themselves.

   * The period of the random number sequence is 2^19937-1.

   * One can save the state of the random number generator with
     `mt_save'.  By loading the state file with `mt_load', one can
     trace a single random number sequence arcoss multiple sessions.

References
     *Note `lrandom': lrandom, *Note `mt_save mt_load': mt_save mt_load.

