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Old 2011-08-31, 01:53   #1
Kosmaj
 
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Question Any interest in yet another sub-megabit drive?

All our drives featuring n<1M are almost over.
Is there interest in one or more new sub-megabit drives?
If so, what starting exponent do you prefer, n=700k or 800k or another one?

As far as I'm concerned I prefer testing n>1M, but of course if we start a new drive I'll test a few files.
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Old 2011-08-31, 03:10   #2
VBCurtis
 
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I think we should continue any k from 8th or 9th drive that is below k=10000 into megabit range. I am not interested in new k's under 1M.

One new drive I would get behind (even if it starts below 1M) is adopting a contiguous range of k's below 10,000 to test together, like Peter has done with 1000-1300. I would suggest we use some of that range, but Peter is easily keeping up on those k's working alone!
-Curtis
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Old 2011-08-31, 08:42   #3
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I would also like the idea suggested by Curtis of testing a contiguous range of k from the k<10000 pool.
According to http://www.rieselprime.de/ all below k=4200 are taken by others (teams or individuals), so we might start from there.

Perhaps, we could provide the test files for the sub-megabit ranges too (e.g. starting from n=700k), so that users with slower machines and/or new team members may pick from those files and others may start from n=1M.
This would also give us the chance of finding some primes before they are getting too small for the Top-5000 list...

BTW.: There are also the high weight k's from the 7th drive, we could start with from n=1M.
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Old 2011-08-31, 09:09   #4
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I would be interested in something sub-megabit. A contiguous range would be a good idea and seems to be quite popular!
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Old 2011-08-31, 17:39   #5
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I am prepared to transfer k=4003-4199 to RPS if people are interested. I have searched it from n=500k-800k and it is getting close to the point where the work involved will be greater than my available resources. There are about 2900 candidates per 1000n, so a bit less work than the 9th Drive. Note that k=4153 was searched to n=1M by Beyond before he knew that I had the range reserved. k=4001 could also be added from 1M.
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Old 2011-09-01, 03:12   #6
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I think amphoria's range is a must-do; do we wish to extend the range above 4200? We could run 4003 up to 4300 or 4400 starting at 800k, and also start a sub-drive to get 4201-4300 or 4400 'caught up' from top5000 cutoff to 800k.

My personal opinion is that the 9th drive is a bit big, so 4003-4199 sounds just right to adopt. If it goes quickly, we can start another one on 4201-4399 without much effort- and this also has the nice effect of having drives available at multiple n-ranges like we've done for so long.

So, how about a continuation of 7th and 8th drive k's at 1M, and also 4003-4199 at wherever it is now?
-Curtis
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Old 2011-09-01, 07:21   #7
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Okay, thanks for your replies.

Then, we'll start another sub-megabit drive very soon.
Next, we have to decide on exponents and based on that on coefficients (k).

I think n=700k is a bit too low. PrimeGrid guys reported 30 Proth primes at around n=690k yesterday and will reach 700k soon. Here are current, approximate ranks of some primes with "milestone" exponents on Top-5000:
n=700k ... 3150
n=750k ... 2500
n=800k ... 2050
Please suggest the starting n: 700k, 750k or 800k (or another one).

k's between 4003 and 4199 are fine if we start at 800k.
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Old 2011-09-01, 12:15   #8
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Perhaps this helps for the decision about the starting point:

For k=4000-4200 the FFT length changes:
at n=700k (48k --> 56k)
at n=814k (--> 64k)
at n=931k (--> 72k)

Regarding k=1400-2000 and 2000-3000, I'm not sure about NPLB's intentions. So far it seems that they are concentrating on the lower n ranges only, so that we may consider to take them too...
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Old 2011-09-01, 21:11   #9
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I would like to start as low as possible, as I believe there's goodness in cataloging as many primes as we can find.

re: Thomas' idea, it's a tough spot. NPLB does not have the resources to test all of 1400-3000 even to keep up with 5000th place, but Gary is nothing if not territorial and rather unlikely to quietly cede any of that range. If I am wrong about his interests and they realize they can't do it all, I'd vote for 2000-2300- that way, we'd have 5-300, 1001-1300 (peter), 2001-2300.
-Curtis
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Old 2011-09-01, 22:19   #10
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Quote:
Originally Posted by VBCurtis View Post
re: Thomas' idea, it's a tough spot. NPLB does not have the resources to test all of 1400-3000 even to keep up with 5000th place, but Gary is nothing if not territorial and rather unlikely to quietly cede any of that range. If I am wrong about his interests and they realize they can't do it all, I'd vote for 2000-2300- that way, we'd have 5-300, 1001-1300 (peter), 2001-2300.
If you want to go with 2001-2300 then, in this instance, I would be surprised if Gary does anything, as he effectively give up on k>2000 in favour of prioritising k=1400-2000. The NPLB Drive that covered k>2000 was terminated several month ago. However note that I have already searched 15 k's in this range to n=1M and a few others are already reserved by RPS members.

Last fiddled with by amphoria on 2011-09-01 at 22:31
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Old 2011-09-02, 10:48   #11
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We'd definitely like to avoid troubles, but I just checked Top-5000, and found that all Riesel primes with 2000 < k < 3000 posted since 2009 were reported by RPS members! Which means that nobody else is searching for them.

So, how about Ks in the 2000-2300 range, excluding already searched ones, starting at n=700k ?

k = 2235, 2265, 2295 from our 7th Drive should be excluded as well.

Dave, can you post the ones you already tested?

Last fiddled with by Kosmaj on 2011-09-02 at 10:51
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