Prime numbers are numbers that are divisible by themselves only and one.
The series begins 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37 and continues (possibly) into infinity.
They can only be checked in reverse - meaning, there is no formula that will create a prime number, only formulas that factor and check if a number is prime. Is it possible to create a formula that will predict all prime numbers?
And when we have that solved, what is the formula that will create or predict all Mersennes Primes?
Email me the answer, but be sure to take credit for it first.
Curious? Further reading: http://en.wikipedia.org/wiki/Prime_Numbers, http://en.wikipedia.org/wiki/Mersenne_prime, http://primes.utm.edu/mersenne/index.html