The Rule 30 Fault Line

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Rule 30 of the elementary cellular automata (CA) was among the first rules in which Stephen Wolfram noticed the appearance of intrinsic randomness in a deterministic system. When initialized with a single black pixel there is patterned behavior down both sides of the unfolding CA which gives way to the randomly patterned center. In fact, Mathematica uses the center column of pixel values as one of its random number generators.