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SOME POPULAR PRN GENERATORS
Numbers uniformly distributed in [0,1]
Multiplicative Linear Congruential
(suggested by Lehmer 1951)
xi º mod [(a xi-1 + c), m]
x0= initial seed a,c,xi are integers in [0,m-1]
m = 2t ; t º # bits for integer representation
maximal period m
e. g.: m =24, a = 3, c = 1, x0= 2
2, 7, 6, 3, 10, 15, 14, 11, 2, 7,¼ period =8
IBM generator RANDU in 60's and 70's: a = 65539, c = 0,
m =229 not recommended by today's standards