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The universal cellular automaton emulating elementary rule 254
The universal cellular automaton emulating elementary rule 254 2
The universal cellular automaton emulating elementary rule 254 3
The universal cellular automaton emulating elementary rule 254. Each cell in rule 254 is represented by a block of 20 cells in the universal cellular automaton. Each of these blocks encodes both the color of the cell it represents, and the rule for updating this color.

From Stephen Wolfram: A New Kind of Science [citation]