RANDU

RANDU is a linear congruential pseudorandom number generator of the Park–Miller type, which has been used since the 1960s. It is defined by the recurrence:

with the initial seed number, ${\displaystyle \scriptstyle V_{0}}$ as an odd number. It generates pseudorandom integers ${\displaystyle \scriptstyle V_{j}}$ which are uniformly distributed in the interval [1, 2³¹ − 1], but in practical applications are often mapped into pseudorandom rationals ${\displaystyle \scriptstyle X_{j}}$ in the interval (0, 1), by the formula:

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