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- Rather, one usually employs a deterministic method which gives
``essentially'' random numbers. These are called pseudorandom.
- Most ``standard'' library random number generators use the so
called linear congruential generators which generate a sequence of
integers
by
- Here, m is called the modulus, a is called the multiplier,
and c is called the increment.
- This is deterministic---given any seed
, one generates an
identical sequence 
, 
, 
- There are most m possible random numbers, but there may be
less. One could generate a cycle if
- Then
, etc. Also, 
and in particular 
.
Geoffrey Fox, Northeast Parallel Architectures Center at Syracuse University, gcf@npac.syr.edu