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Searching for Spaceships

David Eppstein
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Abstract

We describe software that searches for spaceships in Conway's Game of Life and related two-dimensional cellular automata. Our program searches through a state space related to the de Bruijn graph of the automaton, using a method that combines features of breadth first and iterative deepening search, and includes fast bit-parallel graph reachability and path enumeration algorithms for finding the successors of each state. Successful results include a new 2c/7 spaceship in Life, found by searching a space with 2^126 states.

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David Eppstein. 2000-04-26. Searching for Spaceships. https://arxiv.org/abs/cs/0004003

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