A very high-speed digital number sieve

A method is presented to sift numbers satisfying a set of linear congruences from among a large set of numbers. The important properties of the resulting special-purpose device are that a relatively large set of numbers is processed essentially within the time required for performing a shift of one position in an ordinary shiftregister, and that no memory references are necessary. This leads to an over-all speed gain of about three orders of magnitude over modern present-day computers such as the IBM 7090. By combining the device with a general-purpose computer, the size of problems that can be run is greatly increased with almost no decrease in speed. (Author)