The sum of their reciprocals is the Erdos Borwein constant, which is approximately 1.607, and to find the Nth one, S sub n minus two must be zero modulo N according to the Lucas Lehmer test. Their namesake also names a "twister" used to generate random numbers and these numbers are being continuously scouted for by the GIMPS program. Currently only 46 examples are known of, for 10 points, what numbers, which can be expressed in the form 2 raised 
The sum of their reciprocals is the Erdos Borwein constant, which is approximately 1.607, and to find the Nth one, S sub n minus two must be zero modulo N according to the Lucas Lehmer test. Their namesake also names a "twister" used to generate random numbers and these numbers are being continuously scouted for by the GIMPS program. Currently only 46 examples are known of, for 10 points, what numbers, which can be expressed in the form 2 raised to the n minus 1 and are named for a French mathematician.
The sum of their reciprocals is the Erdos Borwein constant, which is approximately 1.607, and to find the Nth one, S sub n minus two must be zero modulo N according to the Lucas Lehmer test.
{Mersenne} primes [prompt on {primes}]