It is a memory algorithm that can calculate the long-term fate of a given starting configuration for the Conway Life Game, and other similar cellular automata, much faster than would be possible using other algorithms that simulate each intermediate step of the PLC.
The algorithm was invented by Bill Gosper in the 1980s while researching at the Xerox Research Center in Palo Alto.
Hashlife is designed to exploit the myriad of temporal and spatial redundancies that exist in most Life rules. For example, in the Conway Game of Life, many apparently random patterns end up as simple collections of static structures and oscillators.
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