Here's my favorite deterministic PRNG optimizing for implementation simplicity: function random() { random._s = random._s || 11224; // seed ret

Here's my favorite deterministic PRNG optimizing for implementation simplicity: function random() { random._s = random._s || 11224; // seed return (random._s = random._s * 16807 % 2147483647) / 2147483646; } Wikipedia says this approach has been around at least since the 1950s. https://en.wikipedia.org/wiki/Linear_congruential_generator https://en.wikipedia.org/wiki/Linear_congruential_generator