A two-dimensional <a href="https://en.wikipedia.org/wiki/cyclic_cellular_automaton" class="extiw" title="en:cyclic cellular automaton">en:cyclic cellular automaton</a> with 16 states, on a 300×300 torus, after 400 steps starting from a random initial configuration. At this stage in the automaton's evolution, three different types of pattern can be seen: random fields similar to the starting configuration, large blocks of color, and spirals. Eventually the spirals will take over the entire field.
<a href="https://en.wikipedia.org/wiki/User:David_Eppstein" class="extiw" title="wikipedia:User:David Eppstein">David Eppstein</a> at <a href="https://en.wikipedia.org/wiki/" class="extiw" title="wikipedia:">English Wikipedia</a>
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