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Followers can then benefit from the map-reading and route-selection skills of the leaders . A three-row array with 4j + 3 columns requires as many curves as rows , he concluded . ( 1854-1912 ) and others demonstrated that , in general , it is impossible to obtain a general solution , expressed as an explicit formula , to the three-body problem . A Turing machine is somewhat like a typewriter whose characters can be put together in countless different ways . The government wants the records preserved for possible use in criminal investigations .