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1) Message boards : Sophie Germain Prime Search : Sophie Germain Prime Search (Message 17470)
Posted 4328 days ago by Michael (MooooMoo)
What's so special about Sophie Germain primes? The 2p+1 definition seems kind of arbitrary. Why not 3p + 2? I can think of a few - 5 and 17, 23 and 71, etc. Or 6p + 1? 7 and 43 match that too.

I know you included links, but the only thing interesting about them is that they were once mentioned in a movie.
2) Message boards : Twin Prime Search : Future direction of TPS (Message 11126)
Posted 4634 days ago by Michael (MooooMoo)
I don't know whether most people have noticed this yet, but there's a new thread on the TPS forum discussing what we should do after finishing n=333333:

Contributions are welcome.
3) Message boards : PrimeGrid : It\'s official...PG & TPS split credit (Message 5858)
Posted 5127 days ago by Michael (MooooMoo)
The only way I could see programs sharing credit is if two primality or two sieving programs were used in the search. For example, openPFGW and LLR or multisieve and gcwsieve. I think primality and sieving should exist on their own. However, within each group, they should share the credit.

Good idea. This would certainly solve cases like this:

where 3!!! sieving programs and 2 primality testing programs were used. Considering the size of the prime, this issue seems quite important.
4) Message boards : PrimeGrid : It\'s official...PG & TPS split credit (Message 5854)
Posted 5128 days ago by Michael (MooooMoo)
So, the adjustment has been done, and TPS/PG have their prime count reduced by 2. However, the programs "LLR" and "NewPGen" are still each getting full credit for the same work. That is, if no other projects or individuals used LLR or NewPGen, LLR and NewPGen would still have a prime count of nearly 1000 on this page:

and not a count of almost 500.

What gives? Why is one standard being applied for projects, and another standard being applied for programs?

(I also posted this on the TPS forum, and didn't get an answer so far)
5) Message boards : Number crunching : SETI.Germany takes #1 spot (Message 5826)
Posted 5133 days ago by Michael (MooooMoo)
A little off topic, but someone from SETI Germany forgot to credit PrimeGrid in addition to TPS:
6) Message boards : Number crunching : #1 (Message 5662)
Posted 5154 days ago by Michael (MooooMoo)
We are now number one with 625 primes.

Congrats guys!

Congrats everyone! The #1 spot came a lot earlier than we thought:

P.S. Hope you get your 100th prime soon, Skligmund. Just three to go ;)
7) Message boards : Number crunching : #2 (Message 5578)
Posted 5163 days ago by Michael (MooooMoo)

I was wondering, though, since PrimeGrid's TPS division uses prime numbers of the form k*2n + 1 and k*2n - 1, and Riesel Sieve does k*2n - 1 only, maybe PrimeGrid could make use of Riesel Sieve's results and save itself a lot of time by not having two different projects having to check the same k*2n - 1 numbers separately to see if they are prime. Of course, PrimeGrid/TPS would still be solely doing their k*2n + 1 numbers.

Unfortunately, PG/TPS cannot make use of Riesel Sieve's results. This is because Riesel Sieve is focused on low k values (below 510,000) and high n values (above 1,000,000). On the other hand, PG/TPS is searching for twins, which have high k values (1,000,000,000 and above) and a lower n value (333,333 and later 500,000).

So in summary, there is no overlap between PG/TPS and RieselSieve in terms of k and n values.
8) Message boards : Number crunching : #2 (Message 5562)
Posted 5164 days ago by Michael (MooooMoo)
Congrats on reaching #2.

However, not to be a spoiler or anything...but please note there's still a possibility that PG and TPS will be adjusted to split the credits. PG is still being evaluated.

Don’t worry too would only move PG back to #3.

Good news...eventual #1 is almost a certainty. The only variable is time.

Also, as Rytis points out, PG is #2 based on prime count. It's #11 based on score. Of course, GIMPS is #1. It holds the top 6 ranked primes. PG's top prime (as of 5/3/07) is ranked 3370.

For more info on scores:

To move up in the score category, PG will have to find "higher value" primes. Right now, the best PG can do is to flood the top 5000 with primes at n=333,333 for k*2^n-1.

Keep up the good work everyone!

You could just count PG and TPS as one project, then, to avoid splitting the credits. Right now, the list is:

1.) Prime Internet Eisenstein Search
2.) PG
2.) TPS
4.) Riesel Prime Search
...everything else

Combining the projects would result in:

1.) Prime Internet Eisenstein Search
2.) PG
2.) TPS
3.) Riesel Prime Search
...everything else


1.) Prime Internet Eisenstein Search
2.) PG and TPS
3.) Riesel Prime Search
...everything else

Either way, everyone benefits. TPS will still be #2 along with PG, and the other projects get to move up a notch.

On another note, why is TPS being singled out for this? I noticed that there are several sieving projects (GFN 2^14 Sieving project, GFN 2^15 sieving project, GFN 2^16 sieving project, and GFN 2^17 sieving project) that take up their own space on the top 20 lists:
9) Message boards : Number crunching : Please submit your primes!!! (Message 5126)
Posted 5213 days ago by Michael (MooooMoo)
It looks like someone (don't know whose username it is) forgot to credit PrimeGrid and TPS:

10) Message boards : PrimeGrid : Top Projects in the Top 5000 Primes List (Message 4643)
Posted 5256 days ago by Michael (MooooMoo)
We're 2 reported primes away from making into top 20 list :) I've sent out emails to the finders so that they can report the found primes.

We made it!

We're at the #19 spot.

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