🚀 go-pugleaf

   The best way to do it, unless you're into native code, is to use
several prime numbers as multipliers, a prime as the modulus, and
give up a few numbers.  I've been playing with a 16-bitter that uses
numbers like 7411 etc for multipliers, and 65521 for the modulus.  With
5 of these multipliers, I get periods that are well beyond 10 million;
I haven't had the patience to wait until the sequence repeats.  It's
slower than lesser generators, but I think you'll agree that such a
period is remarkable for 16 bit arithmetic.
   The key is that you use LONGCARDs to hold the result and avoid getting
cut off at the knees.
   This will work for you, but is not canned code I can pass alon since
it is proprietary.  The principle works with all numbers, though.
   What I suggest you also do is have counts to see to it you don't
fall into a "hole".  Some choices of multipliers for the linear
congruential method deteriorate into subcycle generators (one of the reasons 
for using primes to begin with; they tend not to suffer from
this).  The reason for the longer period is that you get intermixed
combinations from each of the LCG's you use.  
   This method fares poorly on the spectral test, but it does produce
good pseudo-random sequences.

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