Rule 158


Rule 158 is one of the elementary cellular automaton rules introduced by Stephen Wolfram in 1983 (Wolfram 1983, 2002). It specifies the next color in a cell, depending on its color and its immediate neighbors. Its rule outcomes are encoded in the binary representation 58=10011110_2. This rule is illustrated above together with the evolution of a single black cell it produces after 15 steps (Wolfram 2002, p. 55).

The mirror image, complement, and mirror complement are rules 214, 134, and 148, respectively.

Starting with a single black cell, successive generations n=0, 1, ... are given by interpreting the numbers 1, 7, 29, 115, 477, 1843, 7645, ... (OEIS A118171) in binary, namely 1, 111, 11101, 1110011, 111011101, ... (OEIS A118172).

The decimal value of the nth iteration is given in closed form by


(E. W. Weisstein, Apr. 13, 2006), so computation of rule 54 is computationally reducible for an initial configuration consisting of a single black cell. a(n) has generating function


See also

Elementary Cellular Automaton, Rule 30, Rule 50, Rule 54, Rule 60, Rule 62, Rule 90, Rule 94, Rule 102, Rule 110, Rule 126, Rule 150, Rule 182, Rule 188, Rule 190, Rule 220, Rule 222

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Sloane, N. J. A. Sequences A118171 and A118172 in "The On-Line Encyclopedia of Integer Sequences."Wolfram, S. "Statistical Mechanics of Cellular Automata." Rev. Mod. Phys. 55, 601-644, 1983.Wolfram, S. A New Kind of Science. Champaign, IL: Wolfram Media, pp. 55, 90, and 952, 2002.

Referenced on Wolfram|Alpha

Rule 158

Cite this as:

Weisstein, Eric W. "Rule 158." From MathWorld--A Wolfram Web Resource.

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