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Largest Mersenne Prime

Date: 19 Jan 1995 19:09:59 -0500
From: Al Voss
Subject: Largest Mersenne Prime

What is the largest currently known Mersenne prime?

Al Voss 

Date: 19 Jan 1995 19:44:16 -0500
From: Dr. Ken
Subject: Re: Largest Mersenne Prime

Hello there!

According to my sources, the largest known Mersenne Prime is 
2^216091 - 1. It is also the largest known prime of any kind.  

You sound like you already know some stuff about Mersenne primes, 
so I won't elaborate.

-Ken "Dr." Math

Date: 20 Jan 1995 12:29:55 -0500
From: Al Voss
Subject: Re: Largest Mersenne Prime

Thanks for your prompt reply.  I have now found from another 
source that the latest Mersenne Prime known is 2^859433, which is 
the 33rd.  However the discovery date is in question, being either 
in 1993 or 1994.  Do you have a way to check on the proper date?  
I appreciate your help and think that the Dr. Math idea is a good 


Date: 6/21/96 at 1:49:56
From: Jeff Woods
Subject: Footnote to Largest Marsenne Prime Discovery

Check out   

This page has MANY links, including one to Chris's definitive list 
of the top primes, when and by whom they were discovered, etc. 
There is a a comprehensive distributed Pentium challenge under way 
to locate an even larger one than Slowinski's January 1994 
discovery of M859433, which is not necessarily the 33rd one 
overall, just the 33rd one found. The range between M216091 and 
M859433 has not been exhaustively searched yet, though it is known 
that M216091 is indeed the 31st Marsenne prime.

Perhaps soon we'll be able to say for sure if M859433 is indeed 
the 33rd Marsenne prime.

For more on prime numbers, see the Dr. Math FAQ at   

Associated Topics:
College Number Theory

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