SWI-Prolog 5.11.18 Reference Manual: Section 4.27

## 4.27 Misc arithmetic support predicates

set_random(+Option)
  Controls the random number generator that accessible through the function random/1 . Note that the library `library(random)` provides distinct support for random numbers that is not affected by set_random/1.
  seed(+Seed)
    Set the seed of the random generator for this thread. Seed is an integer or the atom `random`. If `random`, repeat the initialization procedure described with the function random/1. Here is an example:

        ?- set_random(seed(111)), A is random(6).
        A = 5.
        ?- set_random(seed(111)), A is random(6).
        A = 5.