An eight-bit rule, provably universal

Each cell looks at itself and its two neighbours and updates by the rule numbered 110 in binary (01101110). The pattern that grows from a single dot encodes computations — Matthew Cook proved (conjectured by Wolfram) that this single rule is Turing-complete. The simplest known universal machine you can describe in a tweet.

rule N · bit k of N = next state of pattern k

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