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Welcome to the “Drive for Five” Challenge
PrimeGrid is attempting to reach n=5 million for 321 Search (currently at n~4.4M).
321 Search began in February 2003 by Paul Underwood and grew into a distributed prime search effort for the form 3*2^n-1. The initial goal was to build upon the completed work at Proth Search and extend the list of known primes to an exponent of 1 million (n=1M). That was quickly achieved so they advanced their goal to finding a mega prime for which they sieved up to n=5M.
As seen on PrimeGrid’s front page, that goal was achieved on 23 Mar 2008, 7:57:28 UTC, when Dylan Bennett of Canada returned a positive result for n=4235414 (3*2^4235414-1). official announcement | decimal representation
Now all that’s left is to complete the sieved work up to n=5M. Thus the name “Drive for Five”. There’s still a chance that a mega prime exists between now and n=5M.
The Challenge will begin 15 May 2008 00:00 UTC and end 1 June 2008 00:00 UTC or until all WU’s have been completed, whichever comes first. Application builds are available for Linux 32 bit and Windows 32 bit. These applications will be sent to 64 bit clients. Unlike the “Ides of March” Challenge, there is no advantage of 64 bit over 32 bit this time.
ATTENTION: This Challenge is not for the weak of heart. WU’s will take a minimum of 6.5 hours on fast computers (C2Q 2.4GHz) and upwards of 15 hours on slower computers (Athlon64 2.1GHz). It is HIGHLY RECOMMENDED that your systems be stable as the primality program LLR does not tolerate "even the slightest of errors." Please see this post for more details on how you can "stress test" your computer: http://www.primegrid.com/forum_thread.p ... =true#8317
Scores will be kept for individuals and teams. Only WU’s that are issued and returned with a valid result during the Challenge dates will be counted. We will use the “prime score” method which is based on the n value (3*2^n-1) to score the challenge. The only difference is that the primary and double checker of a WU will receive the same score.
Therefore, each completed WU will earn a unique score based on its n value. The higher the n, the higher the score. For more information on scoring, see this thread: http://www.primegrid.com/forum_thread.p ... =true#8728.
Please come join the challenge and help 321 Search complete a GREAT journey.
Best of Luck in wrapping up the initial stage of the 321 Search AND to hopefully finding another MEGA PRIME!!!

Additional Information
The “Drive for Five” is part of PrimeGrid’s Challenge series.
Once 321 Prime Search has been completed to n=5M, we will switch over to the +1 form (3*2^n+1). Currently, that prime search is in the Project Staging Area and is ready to enter BOINC as soon as -1 is complete to 5M. WU's are availabe now in LLRNet if you are interested in testing.
We will then take +1 to n=5M. Afterwards, we'll combine 32-1 and 32+1 together and take both up to n=10M. In that range, we expect another 4-6 Mega Primes!

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