sentence1: The two primes were announced by GIMPS on September 16. Before these two discoveries, the two previously largest known prime numbers were discovered by UCMO professors Curtis Cooper and Steven Boone in Missouri, United States, and their record lasted almost three years. Historically, prime numbers discovered by GIMPS are larger than the one previously found. The only other exception was when the 29th Mersenne prime was discovered after the 30th and 31st were found. Founded by M.I.T. graduate George Woltman in 1996, GIMPS has found 12 Mersenne primes, or about one per year on average. Volunteers who wish to help find primes can download a program called Prime95, which runs in the background. Smaller prime numbers, such as those with a few hundred digits, are often used in cryptography.
sentence2: GIMPS was founded by George Woltman.