Garden of Eden/Snippet
A Garden of Eden is a pattern that has no parents and thus can only occur in generation 0. The term was first used in connection with cellular automata by John W. Tukey, many years before Conway's Game of Life was conceived. It was known from the start that Gardens of Eden exist in Life because of a theorem by Edward Moore that guarantees their existence in a wide class of cellular automata. The first Garden of Eden was found by Roger Banks and the MIT group in 1971. It had a bounding box of size 33×9 and 226 cells. Jean Hardouin-Duparc found the second and third Gardens of Eden by computer search in 1973, which had bounding boxes of size 122×6 and 117×6. His goal was to find Gardens of Eden with minimal height. In April 2016, Steven Eker found a Garden of Eden fitting inside a 5×83 bounding box. It is known that no Gardens of Eden exist with height less than 4, but the question is still open for the h=4 case.