The largest known prime is the Mersenne prime described above. The largest known non-Mersenne prime, is , discovered by Brown, Noll, Parady, Smith, Smith, and Zarantonello.

Throughout history, the largest known prime has almost always been a Mersenne prime; the period between Brown et al's discovery in August 1989 and Slowinski & Gage's in March 1992 is one of the few exceptions.

You can help find more primes. For more information see: The Great Internet Mersenne Prime Search home page on http://www.mersenne.org

**References**

*Brown, Noll, Parady, Smith, Smith, and Zarantonello.* **Letter
to the editor.** *American Mathematical Monthly,* vol. 97, 1990, p. 214.

Mon Feb 23 16:26:48 EST 1998