The definition demonstrates how to create a 3D structure using the memory of a 2D Game of Life Cellular Automata.
This is the most famous cellular automata ever invented. People have been discovering patterns for this rule since around 1970. Large collections are available on the Internet.
The rule definition is very simple: a living cell remains alive only when surrounded by 2 or 3 living neighbors, otherwise it dies of loneliness or overcrowding. A dead cell comes to life when it has exactly 3 living neighbors.
A rule by John Conway.
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