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John
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Message 12316 - Posted: 27 Dec 2008 | 17:50:44 UTC
Last modified: 20 Nov 2009 | 21:21:22 UTC

Welcome to the AP26 Search (Arithmetic Progression of 26 primes)

An arithmetic progression is a sequence of numbers with a common difference between any two successive numbers in the sequence. For instance, the sequence 3, 5, 7, 9, 11, 13, 15, ... is an arithmetic progression with a common difference of 2.

Therefore, an arithmetic progression of primes is a sequence of primes with a common difference between any two successive numbers in the sequence. For example 3, 7, 11 is an arithmetic progression of 3 primes with a common difference of 4.

For an arithmetic progression (AP) of primes, AP-k is k primes of the form p + d*n for some d (the common difference between the primes) and k consecutive values of n. The above AP-3 is 3 + 4*n for n=0,1,2.

n=0; 3 + 4*0 = 3 + 0 = 3
n=1; 3 + 4*1 = 3 + 4 = 7
n=2; 3 + 4*2 = 3 + 8 = 11

Another example is the AP-10 of the form 199 + 210*n for n=0..9. This produces the following sequence: 199, 409, 619, 829, 1039, 1249, 1459, 1669, 1879, 2089.

AP-k is also sometimes notated PAP-k (Primes in Arithmetic Progression).

We are searching for the longest AP, not the largest. The current record is an AP-25 discovered May 17, 2008, by Raanan Chermoni & Jaroslaw Wroblewski. For a complete list of records including longest and largest AP's, please see Jens Kruse Andersen's Primes in Arithmetic Progression Records. Also, a list of the top 20 largest AP's can be found at The Prime Pages: The Top 20

Jaroslaw Wroblewski's AP26 code will be used for the search. Geoff Reynolds adapted the program for use with BOINC and for compiling without GMP.

Additional information can be found here:

How to search for 26 primes in arithmetic progression? by Jaroslaw Wroblewski
Primes in arithmetic progression - Wikipedia
Prime Arithmetic Progression - Wolfram MathWorld
arithmetic sequence - The Prime Glossary at the Prime Pages

How to Participate?
Go to your PrimeGrid preferences page and select AP26.

Credit is currently set at 13.61 cobblestones per WU..

WU expectations
Current WU's test 3 K's.
EDIT: WU's now test 6 K's and credit has been doubled.

If K is divisible by one of the primes in the range 29-59, this K is ignored, i.e. AP26 quits instantly. Those are just over 18% of all K�s.

If K is divisible by 61, the time is increased by some 20% over an "ordinary" K and if a few next primes (67, 71, ...) divide K it can be even longer.

Progression of WU's
The arguments for AP26 are Kmin Kmax shift. It correlates with the WU name of ap26_Kmin_Kmax_shift_WU iteration. For example, ap26_1603_1605_0_0 is Kmin=1603, Kmax=1605, shift=0, and initial result.

The WU's will progress linearly up to K=10,000,000. Once 10M has been reached, a new shift will be introduced and included with the previous shift. Then a new shift will be introduced every k=7,000,000 afterwards. For example, after K=10M shift0=, K=1 shift=64 will be started. When shift=64 reaches K=7M, shift=128 will be introduced. At this point there will be 3 different types of WU's, shift 0, 64, and 128.

shift=0 will be at K=17M
shift=64 will be at K=7M and
shift=128 will be at K=1

This goes for another K=7M to produce 4 different WU's.

shift=0 will be at K=24M
shift=64 will be at K=14M
shift=128 will be at K=7M and
shift=192 will be at K=1

and so on until an AP26 is found. :)
____________

[SG]Puzzle-Peter
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Message 12319 - Posted: 27 Dec 2008 | 20:35:32 UTC

First impressions:

10-15 minutes on Q9300@2.7GHz, Ubuntu64
320K RAM per WU

Good stuff for impatient crunchers ;)
____________
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rebirther

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Message 12320 - Posted: 27 Dec 2008 | 20:51:58 UTC
Last modified: 27 Dec 2008 | 20:52:14 UTC

13min = Q9450@3,2 Ubuntu64 8.04 (vmware)
____________

Blast

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Message 12321 - Posted: 27 Dec 2008 | 21:08:18 UTC

Cool, I'll add a few machines to it just for fun. And if 32bit is so slow, just forget about it, there's plenty to do for 32bit machines already.

blah
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Message 12322 - Posted: 27 Dec 2008 | 21:39:12 UTC

8-12 minutes on Q6600@3.2GHz Ubuntu64 8.04

[SG]Puzzle-Peter
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Message 12323 - Posted: 27 Dec 2008 | 21:46:13 UTC

Just had a shortie of 5 minutes. So the range is 5-15min on my machine. Where does this range come from - anything to be seen from the WU name?
____________
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John
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Message 12324 - Posted: 27 Dec 2008 | 22:01:27 UTC - in response to Message 12323.

Just had a shortie of 5 minutes. So the range is 5-15min on my machine. Where does this range come from - anything to be seen from the WU name?

Reading the "How to search for 26 primes in arithmetic progression?" by Jaroslaw Wroblewski will help. It is listed in the first post. :D

Or, keep watching the first post as I continue to update it. :) The latest update may answer your question.
____________

blah
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Message 12325 - Posted: 27 Dec 2008 | 22:32:36 UTC
Last modified: 27 Dec 2008 | 22:48:09 UTC

I had a couple of wu's with compute errors as soon as they started and they have done this on more than one pc.

http://www.primegrid.com/workunit.php?wuid=54671223
http://www.primegrid.com/workunit.php?wuid=54671223

All of the k's in each of these wus are divisible by one of the primes in the range 29-59. So there isn't a valid result from these wu's?

John
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Message 12326 - Posted: 27 Dec 2008 | 22:48:50 UTC - in response to Message 12325.

I had a couple of wu's with compute errors as soon as they started and they have done this on more than one pc.

http://www.primegrid.com/workunit.php?wuid=54671223
http://www.primegrid.com/workunit.php?wuid=54671223

All of the k's in each of these wus are divisible by one of the primes in the range 29-59, so there isn't a valid results from these wu's.

Thanks for the post. Right now these WU's will just error out after 5 failures until we are able to make an exception for the case when all 3 K's are divisible.
____________

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Message 12327 - Posted: 28 Dec 2008 | 0:08:10 UTC

There is a problem with suspend status:

exited with zero status but no finished file
____________

RedGolpe

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Message 12332 - Posted: 28 Dec 2008 | 10:19:37 UTC

The preferences page now gives an error.

Parse error: syntax error, unexpected ')' in /home/boinc/proj/html/project/project_specific_prefs.inc on line 302

Rytis
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Message 12336 - Posted: 28 Dec 2008 | 13:03:55 UTC - in response to Message 12326.

All of the k's in each of these wus are divisible by one of the primes in the range 29-59, so there isn't a valid results from these wu's.

New BOINC versions will now handle these nicely; validator will still reject them though. Working on it.
____________

[BOINC@Poland]emik

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Message 12347 - Posted: 29 Dec 2008 | 5:06:48 UTC

23-24min = T5500@1.66GHz, SuSe11.1 64

John
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Message 12353 - Posted: 29 Dec 2008 | 17:57:45 UTC

Currently 13.61 cobblestones are being granted per WU.
____________

Vato
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Message 12362 - Posted: 29 Dec 2008 | 23:47:56 UTC - in response to Message 12353.

I'm happy with that and it'll keep me crunching AP26.
____________

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Message 12363 - Posted: 30 Dec 2008 | 3:05:21 UTC - in response to Message 12362.

About the introduction message: The app uses Jaroslaw's implementation of his own algorithm, the code I added is mainly to do with adapting the program for use with BOINC and for compiling without GMP.

John
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Message 12367 - Posted: 30 Dec 2008 | 3:42:20 UTC - in response to Message 12363.

About the introduction message: The app uses Jaroslaw's implementation of his own algorithm, the code I added is mainly to do with adapting the program for use with BOINC and for compiling without GMP.

Corrected.

____________

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Message 12410 - Posted: 31 Dec 2008 | 23:52:37 UTC

I think this WU needs to be deleted...

http://www.primegrid.com/orig/workunit.php?wuid=54671728

____________

35 x 2^3587843+1 is prime!

Matthias Lehmkuhl

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Message 12420 - Posted: 1 Jan 2009 | 11:53:05 UTC

There is one other too that causes 0.00 sec runtime and two computers have compute errors
one of this two got this messages
stderr out

<core_client_version>5.10.45</core_client_version>
<![CDATA[
<stderr_txt>
Unrecognized XML in parse_init_data_file: fraction_done_update_period
Skipping: 1.000000
Skipping: /fraction_done_update_period
called boinc_finish
Compiled Oct 17 2008 with GCC 4.1.2 20061115 (prerelease) (Debian 4.1.1-21)
Beginning a new search with parameters from the command line.
0 K in this range remaining to be searched (3 skipped, 0 done).
Checkpoint: KMIN=3625 KMAX=3627 SHIFT=0 K=3628 ITER=0/85 (100.00%)

</stderr_txt>
<message>
<file_xfer_error>
<file_name>ap26_3625_3627_0_1_0</file_name>
<error_code>-161</error_code>
</file_xfer_error>

</message>
]]>

wuid=54678800
____________
Matthias

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Message 12426 - Posted: 1 Jan 2009 | 21:17:18 UTC - in response to Message 12420.

Are there going to be statistics for this search? Such as on the 'Your Account' page, 'Server status' page and/or primestats?
____________

Jarek
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Message 12436 - Posted: 2 Jan 2009 | 14:22:46 UTC - in response to Message 12426.

The WU's that were reported in previous posts as causing errors are those which contain 3 k's divisible by a prime in the range 29-59. They constitute over 0.4% of all WU's, assuming that triples of consecutive k's are grouped to form WU's without any check on the divisibilities.

Also a couple of users on forum BOINC@Poland reported that their computers had problems with receiving new WU's despite a few thousand of WU's available according to the PrimeGrid page.

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Message 12552 - Posted: 5 Jan 2009 | 22:27:06 UTC - in response to Message 12436.

I like the AP26 info on the server status page. :D
____________

Vato
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Message 12673 - Posted: 11 Jan 2009 | 0:00:55 UTC

Can we start counting an AP listed on http://www.primegrid.com/stats_ap26.php as a hit, like we do with primes and factors please?

Especially since this is me! :-)

24, 205619, 468395662504823, 18447

____________

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Message 12690 - Posted: 11 Jan 2009 | 18:16:39 UTC

We have decided that we are not going to count APs as "hits" because of nature of the finds - each workunit actually finds several APs, but they are ignored because they are small, but nevertheless, they are finds. Now, what size is "too small"? That's too hard to decide, so that's the base of our reasoning of NOT to count.
____________

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Message 12695 - Posted: 11 Jan 2009 | 20:52:39 UTC - in response to Message 12690.

True, I spose that would be an issue.

If you did count, I like where you keep stats from (20 and better).
____________

Vato
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Message 12699 - Posted: 12 Jan 2009 | 2:38:46 UTC
Last modified: 12 Jan 2009 | 2:39:34 UTC

I concur - if there are finds interesting enough to have a stats page for, they are interesting enough to count as a hit. If AP19s and shorter aren't interesting enough to hold stats for, don't count them as a hit either.
____________

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Message 12786 - Posted: 16 Jan 2009 | 3:37:11 UTC

The search is only a few weeks old but I was wondering if the results are as expected with the number of work units completed?

All the BOINC stat sites have no trouble displaying my stats, but I get errors from www.primestats.net . I would be grateful for any help fixing this.
____________

Jarek
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Message 12788 - Posted: 16 Jan 2009 | 7:22:06 UTC - in response to Message 12786.

The search is only a few weeks old but I was wondering if the results are as expected with the number of work units completed?

While it is pretty well known how dense single primes are among integers of a given size, estimating density of long arithmetic progressions of primes is very hard, especially when terms of progressions have very different size and not all progressions are on the way of the search program. Therefore I even didn't try to estimate the number of progressions found during early stage of the search, so there are really no expectations to compare the findings with.

I am afraid that the most accurate way of finding the corelation between number of WU's completed and AP's found is to actually start the search and observe the statistics.

Currently the size of progressions found is very different, since the first term can be anywhere in the range 0 - 1.7*10^16, while the difference between the first and the last term is currently 10 times smaller. Later in the search this will become more stable, since the difference in size of progressions searched will not be so large.

At the moment one AP20 or longer is being found on average for each 200-300 WU completed. By the end of the search I would expect the frequency of AP's found to slide down at least by a factor of 5, perhaps even 10 or more, depending on how long we have to search for the first AP26. So my guess would be one AP20 or longer for each 1000-3000 WU at the end of the search.

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Message 12968 - Posted: 24 Jan 2009 | 10:44:48 UTC

So who found the AP25?

Congrats to you!
____________

35 x 2^3587843+1 is prime!

Jarek
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Message 12969 - Posted: 24 Jan 2009 | 11:00:14 UTC - in response to Message 12968.

So who found the AP25?

Congrats to you!

As far as I can read the available data, this is expected rediscovery of the known result.

Owner of the computer, which found it, is: Anonymous

TroubledBunny
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Message 12970 - Posted: 24 Jan 2009 | 11:10:03 UTC

I assumed it was the rediscovery but was still pleased to see it's appearance.

____________

35 x 2^3587843+1 is prime!

Vato
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Message 13813 - Posted: 23 Feb 2009 | 2:29:33 UTC

So we're up to 4 AP24 and a single AP25 - how close are we to hitting untested territory?
____________

Jarek
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Message 13816 - Posted: 23 Feb 2009 | 5:42:52 UTC - in response to Message 13813.

The teritory searched in AP24/AP25 search was a bit irregular and also the search program was set up a bit differently so it was almost impossible to skip the teritory already searched. From the point of view of the whole AP26 search, this teritory is very small and taking it into account was not worth messing up the whole search program and the search schedule. Also it would be almost impossible to isolate a reasonable piece of already searched area which could be taken into account in the current search.

From the beginning we were searching both new and old teritories. At the start the old search area (really impossible to isolate precisely due to prgram setup somewhat incompatible with search ranges in the previos search) was probably around 30% of the current search. However the old search teritory is the best one - containing smaller numbers and having larger density of primes and prime progressions - hence by watching the progressions found, one could get a false impression that we were searching mainly what has already been searched.

Currently we are around K=1,000,000.

The completely uncharted teritory starts at K=5,500,000.

Just before we reach it, we will be searching about 10% of the old area and about 90% of new, but with the old area offering a larger density of AP's.

Vato
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Message 13823 - Posted: 23 Feb 2009 | 9:22:35 UTC

That makes sense - Thanks for the info!
____________

Jarek
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Message 13836 - Posted: 23 Feb 2009 | 15:26:29 UTC - in response to Message 13823.
Last modified: 23 Feb 2009 | 15:27:30 UTC

It looks like we have the first new AP24. This should be announced and reported to Jens Kruse Andersen, who is maintaining the list of all known AP24 and AP25 at
http://users.cybercity.dk/~dsl522332/math/aprecords.htm#ap24

Scott Brown
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Message 14451 - Posted: 18 Mar 2009 | 12:01:43 UTC

Any update on when we might see some record of these on our account pages (e.g., a count of workunits completed, even without "hits" listed)?

____________
141941*2^4299438-1 is prime!

Scott Brown
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Message 14631 - Posted: 1 Apr 2009 | 1:17:44 UTC - in response to Message 14451.

Any update on when we might see some record of these on our account pages (e.g., a count of workunits completed, even without "hits" listed)?

<<BUMP>>
____________
141941*2^4299438-1 is prime!

pschoefer
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Message 14638 - Posted: 2 Apr 2009 | 7:48:19 UTC - in response to Message 14451.

Any update on when we might see some record of these on our account pages (e.g., a count of workunits completed, even without "hits" listed)?

Number of completed tasks is shown now. :)
____________

John
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Message 16689 - Posted: 10 Jul 2009 | 1:55:08 UTC

With this last insert of WU's we have reached K=10,000,000 for shift=0. We will now be alternating inserts between shift=0 and shift=64.

shift=0 will progress from K=10,000,000 to 17,000,000
shift=64 will progress from K=1 to 7,000,000

If we reach those limits without finding the AP26, we'll then advance to shift=128.
____________

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Message 16698 - Posted: 10 Jul 2009 | 8:39:03 UTC - in response to Message 16689.

Excellent progress!

When we find an AP26, I assume we will continue searching for more and hopefully an AP27 will pop out of the woodwork?

____________

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Message 17144 - Posted: 30 Jul 2009 | 4:45:38 UTC

It's not a big deal but when you find something from the AP26 search is it viewable somewhere? I just wanted to see what it was. Thanks, Patrick

AP26 tasks
Completed tests 305
Found of length 21 1

User ID
5913

Scott Brown
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Message 17153 - Posted: 30 Jul 2009 | 12:49:35 UTC - in response to Message 17144.

It's not a big deal but when you find something from the AP26 search is it viewable somewhere? I just wanted to see what it was.

For larger AP, see here.

____________
141941*2^4299438-1 is prime!

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Message 18226 - Posted: 29 Sep 2009 | 19:50:12 UTC
Last modified: 29 Sep 2009 | 20:01:53 UTC

Have plans calculations on the GPU?
____________
Ukraine Distributed Computing

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Message 18245 - Posted: 1 Oct 2009 | 13:00:26 UTC - in response to Message 18226.

Have plans calculations on the GPU?

Yes, I hope soon I will release first public version.

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Message 18249 - Posted: 1 Oct 2009 | 15:59:44 UTC - in response to Message 18245.

Have plans calculations on the GPU?

Yes, I hope soon I will release first public version.

Interesting. Cuda or CAL?
____________

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Message 18252 - Posted: 1 Oct 2009 | 18:29:46 UTC - in response to Message 18249.

Have plans calculations on the GPU?

Yes, I hope soon I will release first public version.

Interesting. Cuda or CAL?

CAL, with cards with double precision support.

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Message 18536 - Posted: 13 Oct 2009 | 11:43:52 UTC - in response to Message 18252.

that's really nice, do you have some stats about speed gains?

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Message 18707 - Posted: 26 Oct 2009 | 17:25:20 UTC

Longer runtimes now?
____________

Lennart SM5YMT
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Message 18708 - Posted: 26 Oct 2009 | 17:37:35 UTC - in response to Message 18707.

Yes 2 times longer and 2* credit :)

Lennart

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Message 18709 - Posted: 26 Oct 2009 | 17:41:14 UTC - in response to Message 18708.

Yes 2 times longer and 2* credit :)

Lennart

Larger searching area?
____________

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Message 18773 - Posted: 2 Nov 2009 | 7:28:09 UTC
Last modified: 2 Nov 2009 | 7:31:21 UTC

With my new 2.8ghz C2D running 32-bit Vista, I'm getting 28-minute times, on the average, for each WU. As the machine is on nearly 24/7, taking what appears to be twice as long to calculate as those with 64-bit systems doesn't bother me.

When you stated that "... 32 bit has such a huge disadvantage in processing time that we are reviewing whether it will be implemented." were you concerned for legacy systems still using 32-bit, or 32-bit systems in general?
____________

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Message 18775 - Posted: 2 Nov 2009 | 7:41:49 UTC - in response to Message 18773.

When you stated that "... 32 bit has such a huge disadvantage in processing time that we are reviewing whether it will be implemented." were you concerned for legacy systems still using 32-bit, or 32-bit systems in general?

32-bit systems in general. The reason is that at the time when those words were written, the speed ratio of available versions 64-bit to 32-bit was something like 8:1.

The main reason for that was that some special kind of 64-bit division is very poorly compiled by 32-bit compilers. Once we recognized the problem, we replaced divisions by proper multiplications, and now the speed of the 32-bit version is reasonable.

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Message 18896 - Posted: 5 Nov 2009 | 17:32:15 UTC

I had a thought today, and I was wondering if anyone with more in-depth knowledge of the AP search could help shed some light on the issue:

It's fairly common knowledge that there is infinitely many prime numbers, but is there any proof (or counterproof) that there is infinitely many AP-k for any given k?

I remember reading elsewhere on these forums that AP29 cannot be found (unless the starting term is 29), but is that a limit of the current search algorithm, or is that something due to the nature of AP29 itself?
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Jarek
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Message 18897 - Posted: 5 Nov 2009 | 17:43:30 UTC - in response to Message 18896.

For any k there are infinitely may AP-k - this is Green-Tao theorem (2004).

The particular search program we are using for the AP26 search, assumes progression difference nondivisible by 29. Hence any progression found by the program has every 29th term divisible by 29. In particular any progression of 29 terms has a term divisible by 29, which is not prime except for highly unlikely case, where this term is equal to 29.

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Message 18900 - Posted: 5 Nov 2009 | 18:32:52 UTC
Last modified: 5 Nov 2009 | 18:33:06 UTC

Reading up on the Tao-Green Theorem, it seems to state that there is at least one AP-k for any given k, but from what I read it doesn't explicitly say anything about there being infinitely many. Maybe the Wikipedia article is not quite clear, or is there something else that lets us assume "if there is at least one, there must be infinitely many"?

Also, if it isn't too much trouble, could you elaborate a little more on the AP29 issue? I haven't been able to figure out for myself why any progression of 29 terms must have a term divisible by 29, unless I misread and you were just talking about within the context of our AP26 search program.

Sorry for all the questions; this stuff is just really interesting to me. I just wish I had a better background in math and could figure some of it out by myself.
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Message 18906 - Posted: 5 Nov 2009 | 19:22:39 UTC - in response to Message 18900.

For any positive integers n, k there exist AP-(n*k) (arithmetic progression of k*n primes). This progression contains n instances of disjoint AP-k. Hence for any n, k there exist at least n AP-k, namely e.g. those contained in some AP-(n*k).
Since n is arbitrary here, there exist arbitrarily many AP-k.

That's how existence of arbitrarily long progressions implies existence of infinitely many progressions of any fixed length.

Note that for example any AP25 contains two AP24, so AP-k in Tao-Green theorem may be a part of a longer prime arithmetic progression. Green-Tao theorem doesn't say that there exist at least one AP-k, which is not a part of AP-(k+1).

As for 29, any existing AP29, which doesn't start with term 29, must have difference divisible by 29. However, the AP26-search program is constructed in such a way, that it assumes progression difference to be NON-divisible by 29 - this is done for simplicity of the code.

Any arithmetic progression of integers must have exactly one of the following two properties:
* progression difference is divisible by 29
* every 29 consecutive terms include exactly one term divisible by 29

John M. Johnson "Novex"
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Message 18907 - Posted: 5 Nov 2009 | 19:23:01 UTC - in response to Message 18900.

Reading up on the Tao-Green Theorem, it seems to state that there is at least one AP-k for any given k, but from what I read it doesn't explicitly say anything about there being infinitely many. Maybe the Wikipedia article is not quite clear, or is there something else that lets us assume "if there is at least one, there must be infinitely many"?

Also, if it isn't too much trouble, could you elaborate a little more on the AP29 issue? I haven't been able to figure out for myself why any progression of 29 terms must have a term divisible by 29, unless I misread and you were just talking about within the context of our AP26 search program.

Sorry for all the questions; this stuff is just really interesting to me. I just wish I had a better background in math and could figure some of it out by myself.

Same here, I wish I knew more in math to be able to figure some of the questions I ask out by myself too. Now you have me curious about the AP29 issue :)
____________

John M. Johnson "Novex"

dlouwe

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Message 18909 - Posted: 5 Nov 2009 | 20:02:24 UTC
Last modified: 5 Nov 2009 | 20:03:34 UTC

Thanks for the explanation, Jarek. That really helped clear things up.

I think the solution for the infinitely many AP-k is really neat. It makes sense that any AP-k will also contain subsets of smaller length k. It's proofs like this that make me so fascinated with math.

Now, I wonder if there is infinitely many AP-k that are not a subset of a longer length k.

Also I'm pretty sure I understand the 29 issue now.

* progression difference is divisible by 29
* every 29 consecutive terms include exactly one term divisible by 29

For these conditions, you could substitute any number, correct? 29 just happens to be a number used by the search program in a way which makes AP29 "invisible" to it.

This is a property of arithmetic progressions that I wasn't aware of previously, but is also incredibly fascinating.
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Message 18910 - Posted: 5 Nov 2009 | 20:12:27 UTC - in response to Message 18909.

* progression difference is divisible by 29
* every 29 consecutive terms include exactly one term divisible by 29

For these conditions, you could substitute any number, correct? 29 just happens to be a number used by the search program in a way which makes AP29 "invisible" to it.

You can substitute any prime number in place of 29. And 29 is the smallest prime larger than the length of the progression we search.

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Message 18911 - Posted: 5 Nov 2009 | 20:16:35 UTC - in response to Message 18910.

Right, thanks for the correction. Should have been obvious, haha.
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Message 18914 - Posted: 5 Nov 2009 | 21:07:48 UTC
Last modified: 5 Nov 2009 | 21:08:51 UTC

Thanks Jarek, I as well understand now about the Ap29 issue, I admit I had to read it twice to fully understand it but it truly is fascinating :)

Edit: As I hit enter on my first post about the ap29 issue you had just hit enter explaining it lol luck of the fast response I guess :) thanks again my friend.
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John M. Johnson "Novex"

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Message 19210 - Posted: 17 Nov 2009 | 19:12:26 UTC

AP 26 Update

We have finally reached the 3rd shift. Actually, we are about 3M behind on this insertion. With our attention on the Challenge, we went right through the "scheduled" insertion point. Currently we have the following 3 shifts:

shift=0; k<19.91M
shift=64; k<9.98M
shift=128; k<733K

The next several inserts will be from shift=128 until we reach k=3M. Afterwards inserts will rotate through all 3 shifts.
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Message 20525 - Posted: 24 Jan 2010 | 3:39:26 UTC

AP 26 Update

We have entered the 5th shift. The status of all 5 shifts are as follows:

shift=0; k<33.11M
shift=64; k<23.73M
shift=128; k<16.14M
shift=192; k<9.13M
shift=256; k<1.10M
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Message 22787 - Posted: 25 Apr 2010 | 4:01:04 UTC

AP 26 Update

Success since the last update: AP 26 Found!!! Congratulations to Benoãt Perichon of France.

The project was extended for 7 days to allow those who were on the cusp of their next badge level the chance to achieve it. On 19 April 2010 at 20:00 UTC, the work buffer was no longer refilled.

The queue is slowly making its way down. Currently, there are 10191 outstanding WU's. The project will be officially closed once these WU's are returned and credited.

Good progress is being made on developing another GPU application using ppsieve which can be implemented in the PPS sieve. As for the PS3, currently the only work available at PrimeGrid is in the PSA using PRPNet. For more information, please read the previous links as well as: Servers recommended for my PS3

As for those who wish to continue on their own to seek a 2nd AP26 (or more AP25's and shorter), the following were the limits reached in PrimeGrid's AP26 search.

shift=0; k<43902416
shift=64; k<33973721
shift=128; k<25165464
shift=192; k<16288724
shift=256; k<9354514
shift=320; k<2751343

AP26 has been removed from the front page "Available" work section as well as the current projects section. Eventually, this Subproject forum will be moved to the Completed subprojects section.

Thanks again to everyone who helped with this effort. It was an excellent success.
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Message 22806 - Posted: 27 Apr 2010 | 0:54:16 UTC

Might be nice to remove it from the preferences then so nobody selects it as their single project.

John
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Message 22807 - Posted: 27 Apr 2010 | 1:54:34 UTC - in response to Message 22806.
Last modified: 12 May 2010 | 14:25:12 UTC

Might be nice to remove it from the preferences then so nobody selects it as their single project.

There is still outstanding work. Once all work is completed, it will be removed.

[EDIT]
3807 outstanding tasks as of 2010-04-27 01:56:09 UTC
2081 outstanding tasks as of 2010-04-27 21:52:52 UTC
1482 outstanding tasks as of 2010-04-28 18:22:44 UTC
847 outstanding tasks as of 2010-05-01 04:28:16 UTC
655 outstanding tasks as of 2010-05-02 12:43:24 UTC
390 outstanding tasks as of 2010-05-03 14:19:19 UTC
109 outstanding tasks as of 2010-05-07 16:27:46 UTC
48 outstanding tasks as of 2010-05-10 03:25:50 UTC
9 outstanding tasks as of 2010-05-12 14:24:01 UTC
____________

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Message 22874 - Posted: 2 May 2010 | 11:02:45 UTC - in response to Message 22807.

If all work is completed, the mark of supported platforms, PS3 and Solaris, is off from PrimeGrid main page?

John
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Message 22876 - Posted: 2 May 2010 | 12:45:43 UTC - in response to Message 22874.

If all work is completed, the mark of supported platforms, PS3 and Solaris, is off from PrimeGrid main page?

Yes, when all work is complete, we can remove that distinction. Please monitor the post before yours to see the remaining work.
____________

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Message 22932 - Posted: 7 May 2010 | 16:13:28 UTC - in response to Message 22807.

How may WU's remain?

Thanks.

Rytis
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Message 22934 - Posted: 7 May 2010 | 16:59:26 UTC
Last modified: 7 May 2010 | 17:04:07 UTC

109.
____________

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Message 23763 - Posted: 13 May 2010 | 22:12:03 UTC

AP 26 Update

The last remaining tasks have been completed, returned, and validated. There are currently 0 outstanding tasks! Congratulations everyone!!!

Over the next few days, this project will be closed up and the thread will be moved to the "Completed subprojects" section.

[EDIT]
3807 outstanding tasks as of 2010-04-27 01:56:09 UTC
2081 outstanding tasks as of 2010-04-27 21:52:52 UTC
1482 outstanding tasks as of 2010-04-28 18:22:44 UTC
847 outstanding tasks as of 2010-05-01 04:28:16 UTC
655 outstanding tasks as of 2010-05-02 12:43:24 UTC
390 outstanding tasks as of 2010-05-03 14:19:19 UTC
109 outstanding tasks as of 2010-05-07 16:27:46 UTC
48 outstanding tasks as of 2010-05-10 03:25:50 UTC
9 outstanding tasks as of 2010-05-12 14:24:01 UTC
0 outstanding tasks as of 2010-05-13 22:08:00 UTC
____________

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Message 23832 - Posted: 17 May 2010 | 15:37:42 UTC

I'm rather sad that I missed this project, I only recently got back into boinc processing. Congratulations on finding the first AP26.

Jay
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Message 23837 - Posted: 17 May 2010 | 16:58:08 UTC - in response to Message 23832.

I feel the same way. I was just a little too late.
____________

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