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Welcome to the Dog Days of Summer Challenge

Posted: Tue Aug 05, 2008 10:51 am
by UBT - bobuk
Welcome to the Dog Days of Summer Challenge..
We are #9 over all through the 2008 Challenge Series link here:http://www.primegrid.com/challenge/challenge.php#team


QUOTE:
PrimeGrid’s Challenge series continues with the Dog Days of Summer Challenge. Most dictionaries define the Dog Days as follows:

1 : the period between early July and early September when the hot sultry weather of summer usually occurs in the northern hemisphere
2 : a period of stagnation or inactivity

Please come join us in ushering an end to the hot sweltering days of summer. Also, it's been over 4 months since PrimeGrid's last significant prime. Let's break this "prime stagnation" with a new prime. :) A 3 day (72 hour) Challenge is being offered on PrimeGrid’s 321 Prime Search LLR application.

To participate in the Challenge, please select only the 321 Prime Search project in your PrimeGrid preferences section. The challenge will begin 22 August 2008 00:00 UTC and end 25 August 2008 00:00 UTC. Application builds are available for Linux 32 bit and Windows 32 bit. These applications will be sent to 64 bit clients. As with all LLR application projects, there is no advantage of 64 bit over 32 bit.

Here's a link to one of many time zone onverters: The World Clock - Time Zone Converter  http://www.timeanddate.com/worldclock/converter.html

Scoring Information

Scores will be kept for individuals and teams. Only work units issued AFTER 22 August 2008 00:00 UTC and received BEFORE 25 August 2008 00:00 UTC will be considered for credit. We will use the "prime score" method which is based on the n value (k*b^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.

About 321 Prime Search

321 Prime Search is a continuation of Paul Underwood's 321 Search (see below) which looked for primes of the form 3*2^n-1. PrimeGrid has added the +1 form and will eventually be searching for primes beyond the extended n=5M (M=mega, 10^6) goal.

Currently, PrimeGrid is testing only 3*2^n+1 for n<5M (as of this post about n=1.95M). Once all n are completed below 5M, both -1 and +1 forms will be combined and the search will be extended up to n=10M.

Primes known for 3*2^n+1 occur at the following n:

1, 2, 5, 6, 8, 12, 18, 30, 36, 41, 66, 189, 201, 209, 276, 353, 408, 438, 534, 2208, 2816, 3168, 3189, 3912, 20909, 34350, 42294, 42665, 44685, 48150, 54792, 55182, 59973, 80190, 157169, 213321, 303093, 362765, 382449, 709968, 801978, 916773, 1832496, 2145353, 2478785

We are hoping for 2-3 more primes before n=5M with at least one of them being a Mega Prime. :)

What is LLR?

The Lucas-Lehmer-Riesel (LLR) test is a primality test for numbers of the form N = k*2^n − 1, with 2^n > k. Also, LLR is a program developed by Jean Penné that can run the LLR-tests. It includes the Proth test to perform +1 tests and PRP to test non base 2 numbers. See also:

About 321 Search

321 Search began in February 2003 from a post by Paul Underwood seeking help from interested parties in a prime search attempt of 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

During the Drive for Five Challenge, the goal of reaching n=5M was almost achieved. As of 14 July 2008, all but one range has been completed. (the one range is in the manual reservations...PG has completed all of its ranges)

Primes known for 3*2^n-1 occur at the following n:

1, 2, 3, 4, 6, 7, 11, 18, 34, 38, 43, 55, 64, 76, 94, 103, 143, 206, 216, 306, 324, 391, 458, 470, 827, 1274, 3276, 4204, 5134, 7559, 12676, 14898, 18123, 18819, 25690, 26459, 41628, 51387, 71783, 80330, 85687, 88171, 97063, 123630, 155930, 164987, 234760, 414840, 584995, 702038, 727699, 992700, 1201046, 1232255, 2312734, 3136255, 4235414
QUOTE END...

So any help once again is needed to move our team up the rankings...

b.:D

Posted: Sat Aug 23, 2008 7:55 am
by UBT - Nogbo
We are losing ground on this one as we have dropped 2 places overnight.

We were 17th last night and down to 19th this morning   :(

Posted: Sat Aug 23, 2008 8:29 am
by Joshrandom
UBT - Nogbo wrote:We are losing ground on this one as we have dropped 2 places overnight.

We were 17th last night and down to 19th this morning   :(
Since it's only you and me contributing to the teams score Nogbo, I guess we aren't doing too badly.  :wink:

http://www.primegrid.com/challenge/dog_ ... users.html

http://www.primegrid.com/challenge/dog_ ... teams.html

If anyone else cares to join us, remember to select only the 321 prime search project in your Primegrid prefs.

Posted: Sat Aug 23, 2008 11:20 am
by UBT-mark3346
If anyone else cares to join us, remember to select only the 321 prime search project in your Primegrid prefs.
and remember to update your home/work etc preferences if you use them and not just the default ones  :oops:

Posted: Sat Aug 23, 2008 11:37 am
by Ben
I've put a few cores on it now

Posted: Sat Aug 23, 2008 1:42 pm
by Timby
Sorry Bob forgot all about this one, but am on it now  :oops:

Posted: Sat Aug 23, 2008 3:39 pm
by UBT - bobuk
Timby wrote:Sorry Bob forgot all about this one, but am on it now  :oops:
bob did not forget.......see 1st post




b. :D

Posted: Sat Aug 23, 2008 4:34 pm
by UBT - Mikee
I forgot about it as well.

So I've aborted a load of stuff that hadn't started yet.

Runs a bit warm doesn't it! CPU temperature increased from 57 to 63 with 2 cores running - got another 2 to start up yet!

Hopefully, before the evening is out, I'll get a new PC built so this project will be a good test of it!

Posted: Sat Aug 23, 2008 9:22 pm
by UBT - Nogbo
Yeah, we've got company at last  :D

Welcome aboard guys!

Team currently standing at 21st  :(

Posted: Sun Aug 24, 2008 10:36 pm
by UBT-mark3346
To ensure completed wu's count make sure they are reported before the deadline.