The boundaries of one-dimensional, two-color cellular automata depending on four cells and begun from simple initial conditions are systematically studied. The exact growth rates of the boundaries that appear to be reducible are determined. The …
In 1984, Packard [1] introduced simple planar cellular automata to emulate the growth of snow crystals. These Packard Snowflakes have since been popularized by S. Wolfram and others, most recently in [2]. The present paper provides a rigorous …