[QUOTE=Cruelty;344954]7019*10^881309-1 (881313 digits)[/QUOTE]

Awesome!

The depressing part is that I calculate only 19.56% chance of a prime by n=2M for r10.

What is really needed is a fixed-k non-base-2 GPU sieve similar to srsieve :smile:

An excellent reward for three years of persistence. 8579*10^373260-1 seems to have been your previous R10 prime...

Willem.

[QUOTE=Cruelty;344992]What is really needed is a fixed-k non-base-2 GPU sieve similar to srsieve :smile:[/QUOTE]

Unfortunately we are a way from doing that. BSGS needs too much memory so the GPU is not practical. Memory light methods are not very smooth.

[QUOTE=rogue;345012]Unfortunately we are a way from doing that. BSGS needs too much memory so the GPU is not practical. Memory light methods are not very smooth.[/QUOTE]
This has been discussed in the past.
[URL]http://www.mersenneforum.org/showthread.php?t=16250&highlight=bsgs&page=3[/URL]
Is the memory usage dependent on p or the range of p?
Also you talk about needing 256 sets of 80MB data as there are 256 cores. Is there a way to utilize multiple cores on the same set of data?
Another option is to make it use only a few cores(as many as possible) and expect the user to also run a thread of mfaktc to saturate the gpu.

[QUOTE=henryzz;345028]This has been discussed in the past.
[URL]http://www.mersenneforum.org/showthread.php?t=16250&highlight=bsgs&page=3[/URL]
Is the memory usage dependent on p or the range of p?
Also you talk about needing 256 sets of 80MB data as there are 256 cores. Is there a way to utilize multiple cores on the same set of data?
Another option is to make it use only a few cores(as many as possible) and expect the user to also run a thread of mfaktc to saturate the gpu.[/QUOTE]

Memory usage is dependent upon p.

As for multiple cores for each p, I haven't investigated. If that can be done, it might be the way to go.

[QUOTE=rogue;345031]Memory usage is dependent upon p.

As for multiple cores for each p, I haven't investigated. If that can be done, it might be the way to go.[/QUOTE]

It will be about 256 times slower....

[QUOTE=Citrix;345057]It will be about 256 times slower....[/QUOTE]
I didn't expect full speed with multiple cores. I was hoping for better than a linear decrease in speed.

The easiest way of doing this would be:

Suppose you were sieving from k*2^x+1 to k*2^y+1
Then divide the range into 256 pieces

x, x1,x2,xi....y

Then send each range for a fixed p to the GPU core.

Each core will require 1/16 th of the memory needed for the BSGS algorithm.
(Which is generally low for the low weight k's like CRUS; I am not sure how much memory each core has)

Multmods needed will be 2* sqrt (n/256) *256
Since there are 256 cores, multmods will be 2* sqrt (n/256) per core

Overall you will see it is 16 times faster compared to BSGS but requires 16 times more memory.

There are other algorithms that can be implemented with little memory use but at the cost of not finding all but most of the factors.

The only definite way (non-probabilistic) without requiring alot of memory would be brute force (test every n) or index calculus (which will be very cumbersome and hard to implement).

For some of the extremely low weight k's left or small range of n's... brute force can be implemented helping the project out. BSGS might also be implementable for an extremely small n range.

:smile:

Outstanding prime Borys and well deserved! I was hoping base 10 would finally yield one before n=1M.

[URL="http://primes.utm.edu/primes/page.php?id=114845"]74*500^218184-1[/URL] (588874 digits)

[QUOTE][URL="http://primes.utm.edu/primes/page.php?id=114845"]74*500^218184-1[/URL] (588874 digits) [/QUOTE]

Nice one. Makes R500 a 3ker.:bow:

S683 is proven with [URL="http://primes.utm.edu/primes/page.php?id=115157"]18·683^141239+1[/URL].
Residues are in the email. Base released.

Nice one Serge! Any prime that knocks down all of the n=1.29M primes a notch is a good one. :smile:

59506*6^780877+1 is Prime


Lennart

Congrats Lennart! :smile: We were definitely overdue on S6.

S643 is proven with [URL="http://primes.utm.edu/primes/page.php?id=115202"]6·643^164915+1[/URL] (463117 digits)

[QUOTE]S643 is proven with [URL="http://primes.utm.edu/primes/page.php?id=115202"]6·643^164915+1[/URL] (463117 digits) [/QUOTE]Nice again Serge. Told ya they come in pairs.:bow:
I still think we have another S6 in the works.

[URL="http://primes.utm.edu/primes/page.php?id=115249"]48*580^174782 - 1
[/URL]

I also have a [URL="http://primes.utm.edu/primes/page.php?id=115256"]small one[/URL]. Here today, gone tomorrow.

R318
 

That makes R318 a 1ker. Nice

Serge is a prime finding machine lately.:banana:

78*916^120247-1
78*916^122431-1

R916 is proven :cool:

[QUOTE=unconnected;354976]78*916^120247-1
78*916^122431-1

R916 is proven :cool:[/QUOTE]

Very proven one might say :showoff:

[QUOTE=unconnected;354976]78*916^120247-1
78*916^122431-1

R916 is proven :cool:[/QUOTE]

Wow. I think that's the first time that finding 2 primes close together for the same k to prove a base has happened at CRUS. A few years ago, Max and I separately found primes for the same k on S16 in different reserved ranges but it didn't prove the base. I think it also might have happened on our PRPnet server at one time or another but once again, never for a proof.

Congrats!

After a long dry spell: 52*701^163776+1 is prime. At 466063 digits, this will make it in at #5 on the largest CRUS Sierpsinki primes to prove a conjecture.

Nice Mark. It has been a while.:party:

A well-deserved break, Mark! Congrats!

Way to break that dry spell! :smile:

R620
 

R620 is proven with 20*620^120136-1 (335469 digits)
The leading edge of search was at n=136066, completed up to n=124808.
[ATTACH]10371[/ATTACH]
I split up the factors file into 6 and had 5 cores going ahead.
Only recently did I restart the 6th core.
The Prime was in the 6th, so I ended up doing twice as much testing as I had to.
Feeling very happy about it! :smile:
Base released.

SR5 rank 73 in Top 5000
 

[URL="http://primes.utm.edu/primes/page.php?id=116163"]175124*5^1422646-1[/URL] found by David Yost on 31 October 2013

Rank 73 : 994393 digits

Let's revive this thread:

[URL="http://primes.utm.edu/primes/page.php?id=117531"]44*383^143148-1[/URL] is prime 369,782 digits :smile:

Plus of course these 3 previously reported Top5000 primes:

905*2^1742026-1 524,406 digits
7673*2^1464988-1 441,010 digits
47395*2^1361124+1 409,744 digits

Take care :smile:

KEP

Looks like I've found BIG prime today. N+1 test in progress, stay tuned.

It's happened several times on this project: When big primes come, they come in triplet. Yours would be the 3rd over the last several days.

The most unbelievable thing that new prime was found by the same machine and exact the same core which found previous big prime (22*900^252407-1) one week ago!

[QUOTE=unconnected;375556]The most unbelievable thing that new prime was found by the same machine and exact the same core which found previous big prime (22*900^252407-1) one week ago![/QUOTE]

Come on; report it. You're leaving us in suspense. lol :smile:

Can't wait another day to complete N+1 test. So I submit it right now.
Added [URL="http://primes.utm.edu/primes/page.php?id=118016"]118016[/URL] : 653*10^1435026-1 (1435029 digits)

Congrats!? You really should prove it before submission to the top5000 :rant:

[QUOTE=unconnected;375706]Can't wait another day to complete N+1 test. So I submit it right now.
Added [URL="http://primes.utm.edu/primes/page.php?id=118016"]118016[/URL] : 653*10^1435026-1 (1435029 digits)[/QUOTE]

Is this in the right thread? That doesn't appear to be found as part of this project.

Congrats nonetheless.

[QUOTE=unconnected;375706]Can't wait another day to complete N+1 test. So I submit it right now.
Added [URL="http://primes.utm.edu/primes/page.php?id=118016"]118016[/URL] : 653*10^1435026-1 (1435029 digits)[/QUOTE]

42nd on the list! Very impressive! :toot:

[QUOTE=paulunderwood;375707]Congrats!? You really should prove it before submission to the top5000 :rant:[/QUOTE]

I'd guess the first test proved it (i.e. it was an N+1, not a PRP test). As long as we have no reason to doubt the integrity of the test (e.g. experimental software), and the test wasn't just PRP, and the prime isn't mainstream-news-worthy (e.g. new Mersenne), I'm not against submitting it without a double check.
Basically, my impression from the notes and warnings at [url]http://primes.utm.edu/primes/submit.php[/url] is that [I]you[/I] should be convinced that it is proven prime before submitting it.

[QUOTE=unconnected;375706]Can't wait another day to complete N+1 test. So I submit it right now.
Added [URL="http://primes.utm.edu/primes/page.php?id=118016"]118016[/URL] : 653*10^1435026-1 (1435029 digits)[/QUOTE]
Very berry nice! :tu:
And a near rep-unit, too; let [URL="http://homepage2.nifty.com/m_kamada/math/factorizations.htm"]Kamada[/URL] know, he will be thrilled!

[QUOTE=Batalov;375718]Very berry nice! :tu:
And a near rep-unit, too; let [URL="http://homepage2.nifty.com/m_kamada/math/factorizations.htm"]Kamada[/URL] know, he will be thrilled![/QUOTE]

The number is 6529999.....9, which doesn't quite meet any of the named categories I see at the link, since it has exactly three digits different.

[QUOTE=Mini-Geek;375721]The number is 6529999.....9, which doesn't quite meet any of the named categories I see at the link, since it has exactly three digits different.[/QUOTE]
It fits. M.Kamada collects any [URL="http://mada.la.coocan.jp/nrr/prime/primedifficulty.txt"]near- and far- repdigits[/URL], including e.g. 13190078378725094213765678546*10^n-1 (how about his one ;-)

[QUOTE=unconnected;375706]Can't wait another day to complete N+1 test. So I submit it right now.
Added [URL="http://primes.utm.edu/primes/page.php?id=118016"]118016[/URL] : 653*10^1435026-1 (1435029 digits)[/QUOTE]

A HUGE congrats on not only CRUS's largest proof but in shattering the project prime size record by more than 50%. WOW!! The huge primes really do come in triplet on this project. A party is in order:
:bounce wave::groupwave::george::et_::curtisc:


[QUOTE=paulunderwood;375707]Congrats!? You really should prove it before submission to the top5000 :rant:[/QUOTE]

[I]Congrats!? [/I]with a question mark? What's up with that? I disagree with this statement. If a strong PRP test has been run, then it's OK to submit it as prime to the top-5000 while waiting for the primality proof. The reason: There is a greater chance of being struck by lightning 3 times in one day than a strong PRP of this size being composite. I have submitted > 5 PRPs to top-5000 that were still waiting on their primality proof on my machine. There is no reason to delay the inevitable with the small exception mentioned by Tim (Mini-Geek): If there is a big media announcement about the prime.


[QUOTE=rogue;375711]Is this in the right thread? That doesn't appear to be found as part of this project.

Congrats nonetheless.[/QUOTE]

Congrats [I]nonetheless[/I]??? "Nonetheless"...surely you jest. Come on people! What's with the half-hearted congrats? That's two of them now. This prime proves Riesel base 100, i.e.:
653*100^717513-1 is prime!

[QUOTE=Mini-Geek;375712]42nd on the list! Very impressive! :toot:

I'd guess the first test proved it (i.e. it was an N+1, not a PRP test). As long as we have no reason to doubt the integrity of the test (e.g. experimental software), and the test wasn't just PRP, and the prime isn't mainstream-news-worthy (e.g. new Mersenne), I'm not against submitting it without a double check.
Basically, my impression from the notes and warnings at [URL]http://primes.utm.edu/primes/submit.php[/URL] is that [I]you[/I] should be convinced that it is proven prime before submitting it.[/QUOTE]

I still disagree. IMHO It is OK to submit huge strong PRPs to top-5000 that are in the process of being proven (and it is known that they can be proven, i.e. of the form k*b^n-1 or k*b^n+1) if the chance of it not being prime is less than the chance of getting struck by lightning 3 times in one day. lol Regardless, it is nice to know that it had already been proven by an N+1 primality test. Doublechecking before submission is complete overkill unless the media would become involved.

Or perhaps I digress and agree: Based on Tim's last sentence here from a posting on top-5000. For a PRP of this size, I [I]would be convinced[/I] that it is a prime after a strong PRP test so IMHO, that is justification enough for submitting it.

I'm looking forward to seeing CRUS's and Dimitry's score make a huge jump at top-5000. Congrats again Dimitry! :smile: Edit: When the score is applied, we will be only about a score of 50 behind PSP for 5th place on the project score list!

My apologies on your find. I was thinking base 10, not base 100, so I didn't recognize this as proving the conjecture. I must say that I am just a wee bit jealous. :bow:

Well, you would never catch me submitting a PRP for proof by The Prime Pages server. Reasons? There could have been hardware failure. It could be a Carmichael number. I like to be 99.99999 recurring per cent sure, not 99.9999.....9999% :ermm:

[CODE]Command: /home/caldwell/client/pfgw/pfgw64 -tp -q"653*10^1435026-1" 2>&1
PFGW Version 3.7.7.64BIT.20130722.x86_Dev [GWNUM 27.11]
Primality testing 653*10^1435026-1 [N+1, Brillhart-Lehmer-Selfridge]
Running N+1 test using discriminant 3, base 1+sqrt(3)
Calling Brillhart-Lehmer-Selfridge with factored part 69.90%


653*10^1435026-1 is prime! (42902.6019s+0.0287s)
[Elapsed time: 11.92 hours][/CODE]

:party:

N+1 test on my side was finished few minutes ago.
[QUOTE]Primality testing 653*10^1435026-1 [N+1, Brillhart-Lehmer-Selfridge]
Running N+1 test using discriminant 3, base 1+sqrt(3)
653*10^1435026-1 is prime! (293303.4768s+0.0688s)
[/QUOTE]

[QUOTE=paulunderwood;375746]Well, you would never catch me submitting a PRP for proof by The Prime Pages server. Reasons? There could have been hardware failure. It could be a Carmichael number. I like to be 99.99999 recurring per cent sure, not 99.9999.....9999% :ermm:[/QUOTE]

It's possible, though exceedingly unlikely, that unnoticed software glitches or random bit flips could produce a "prime" result in a composite number. Sorry, but you're still dealing with 99.9999.....9999%. The only difference is how many 9's there are (and how mathematically quantifiable that is).

I'd be more inclined to "trust" a number that's passed multiple PRP tests (especially multiple types) than a number that's passed a single deterministic primality test.

99.9 recurring per cent only occurs in theory. In practice, we're only 99.9999.....9999% sure that M57885161 is prime. (granted, this number is close enough to 100% that we, in practice, treat it as 100%)

Also, vaguely on the topic of proving primes: [URL="http://www.mersenneforum.org/showthread.php?t=19425"]LLR vs PFGW speed[/URL] In a quick test on my computer, LLR is [I]far[/I] better for proving this prime. I estimate that I can do it on one core of my CPU in ~7000 seconds (just under 2 hours).

[URL="http://mersenneforum.org/showthread.php?t=19142"]It had happened before[/URL], though. So it is a good thing to blow on cold water ([URL="http://translation.babylon.com/english/Once+burned+by+milk+you+will+blow+on+cold+water/"]Cf.[/URL]), just in case.

One thing that is implied in the above improbability arguments is that "let's say, a random bit flipped -- but the result is still random!" That's not what happens, at least in some implementations. If the whole interim residue is zeroed in (there are hardware failures that do that), then the rest of exponentiation will stay all zeroes. The end result is implementation dependent. P95 catches those zero-ins early, other programs - we don't know for sure (and who has time to read the source, right?).

[QUOTE=Mini-Geek;375758]<snip>
I'd be more inclined to "trust" a number that's passed multiple PRP tests (especially multiple types) than a number that's passed a single deterministic primality test.
[/QUOTE]

Agreed completely.

[QUOTE=Batalov;375760][URL="http://mersenneforum.org/showthread.php?t=19142"]It had happened before[/URL], though. So it is a good thing to blow on cold water ([URL="http://translation.babylon.com/english/Once+burned+by+milk+you+will+blow+on+cold+water/"]Cf.[/URL]), just in case.

One thing that is implied in the above improbability arguments is that "let's say, a random bit flipped -- but the result is still random!" That's not what happens, at least in some implementations. If the whole interim residue is zeroed in (there are hardware failures that do that), then the rest of exponentiation will stay all zeroes. The end result is implementation dependent. P95 catches those zero-ins early, other programs - we don't know for sure (and who has time to read the source, right?).[/QUOTE]

Based on the strong wording on the top-5000 site, I can understand people's reluctance after finding a strong PRP to only wait until there is a "sure fire" proof before submitting a top-5000 prime but there are a couple of more points that I'd like to make:
1. If a bad PRP is found due to a computer glitch, isn't that same glitch just as likely to incorrectly "prove" the "PRP" as "prime"?
2. The example pointed out by Serge is not one that I am referring to. I'm referring to examples where a non-power-of-2 base PRP is found and has yet to be proven like was the case with Dimitry here and has been the case for me in the past. In the example shown by Serge, since it was base 2 I believe there was no PRP test run and the actually primality proof was incorrect due to a computer glitch. A second test on the same computer likely would have incorrectly found it prime again.

Here is what would have to happen for there to be any real risk to reporting a PRP (of the k*b^n+1 or k*b^n-1 form) early, that is it has not been proven yet:

1. A computer would have to have a glitch that incorrectly finds a PRP but its proof finds it composite. Very unlikely. (If it finds it prime, then the bad prime gets reported to top-5000 anyway and eventually rejected so it doesn't matter whether you waited for the primality test or not.)

2. A good computer correctly finds a PRP but the PRP turns out to be a Carmichael number and so the same computer correctly finds the PRP as composite. This composite would have to be top-5000 size at the time that it is incorrectly reported as prime to top-5000. Not likely in any of our lifetimes.*

That's why I feel safe in reporting top-5000 PRPs while my machine is still working on their proof.

If people want to be "sure fire" as is reasonably possible, after a top-5000 size PRP is found, a different computer should be used to prove it prime. Since many people do not have access to their machines for days at a time, this is sure to be a burden.

*If anyone can quote the chances of a top-5000 size 3-PRP being composite, I would like to see them. I have heard figures like 1 in < 10^20. That would have a less chance of happening then winning 2 major lotteries with back-to-back tickets. Clearly computer glitches are more frequent and I believe such glitches are just as likely to report an incorrect PRP as they are to "prove" that same "PRP" as "prime", in which case it doesn't matter if one reported it to the top-5000 site before or after the "proof".

Indeed, for another example, for all prime p, all of the 3[SUP]p[/SUP]+-3[SUP](p+1)/2[/SUP]+1 are PRPs. (3-PRPs, to be exact. In default mode, base 3 is used. Well, devil is in the details, for each p, + or - sign is determined by a simple rule, and for the expression with the opposite sign one has to divide that complement expression by 7... - and [U]both of these[/U] will be PRPs!)

For example:
3^6689+3^3345+1 is 3-PRP and (3^6689-3^3345+1)/7 is 3-PRP
3^6709-3^3355+1 is 3-PRP and (3^6709+3^3355+1)/7 is 3-PRP
...you can go as high as you want, they will be 3-PRPs

But only the few of them are actually (2-)PRPs. One [I]must[/I] use -b2 for the project of searching for these.
And then, all known of those true (2-) PRPs are (Eisenstein-Mersenne) primes [SPOILER]see my "Location" field[/SPOILER]. There's also a known test for these that is faster than the N+-1 test (N+-1 test is also a valid test for them)

[QUOTE=unconnected;375706]Can't wait another day to complete N+1 test. So I submit it right now.
Added [URL="http://primes.utm.edu/primes/page.php?id=118016"]118016[/URL] : 653*10^1435026-1 (1435029 digits)[/QUOTE]

Congratulation! That's a nice one! :bow wave:

I've been ploughing the megadigit terrain for quite some time with various conjectures. Let's try to have the megaprimes coming in those triplets that Gary mentions ;-)

[QUOTE]I've been ploughing the megadigit terrain for quite some time with various conjectures. Let's try to have the megaprimes coming in those triplets that Gary mentions ;-) [/QUOTE]

You certainly are overdue. Start your own triplet.

[QUOTE=unconnected;375706]Can't wait another day to complete N+1 test. So I submit it right now.
Added [URL="http://primes.utm.edu/primes/page.php?id=118016"]118016[/URL] : 653*10^1435026-1 (1435029 digits)[/QUOTE]

Congratulation :smile:

May I come up with a suggestion:

We create a CRUS MegaPrime thread, where all primes with at least 1 million digits, that is found by CRUS members, is listed. I know the moderators may not like such a list, however MegaPrimes is for CRUS still a rare thing and there is now 3 moderators, so the task of maintaining the thread should be one that can be accomplished without being too much of a burden :smile:

Any thoughts?

[URL]http://primes.utm.edu/primes/page.php?id=118060[/URL]

115*26^520277-1 is prime 736181 digits and 214 entry rank

Conjecture proven

Results emailed

[QUOTE=MyDogBuster;376347][URL]http://primes.utm.edu/primes/page.php?id=118060[/URL]

115*26^520277-1 is prime 736181 digits and 214 entry rank

Conjecture proven

Results emailed[/QUOTE]

Congrats on the find.

[QUOTE=MyDogBuster;376347][URL]http://primes.utm.edu/primes/page.php?id=118060[/URL]

115*26^520277-1 is prime 736181 digits and 214 entry rank

Conjecture proven

Results emailed[/QUOTE]

Congrats on a huge proof!! CRUS is really on a roll. That's 3 huge proofs and 4 huge primes in the last 2 weeks.

:bow wave::groupwave::george::chalsall::anurag:

Move discussion about sieving on a GPU vs a CPU to a new thread [URL="http://www.mersenneforum.org/showthread.php?t=19449"]here[/URL].

[QUOTE=MyDogBuster;376347]115*26^520277-1 is prime 736181 digits and 214 entry rank

Conjecture proven[/QUOTE][QUOTE=gd_barnes;376597]Congrats on a huge proof!! CRUS is really on a roll. That's 3 huge proofs and 4 huge primes in the last 2 weeks.[/QUOTE]
Wow, I glossed over those two important words "conjecture proven" the first time a read this...a hearty belated congratulations! :bow: It's always heart-warming to see one of the original bases <32 fall - proofs in that range are so far and few these days, and quite an accomplishment when they do come.

I keep toying with the idea of picking up S9 and trying to knock out its last k...maybe after we've gotten R6 to 2M.

R1024 just became a 1-ker
 

[QUOTE][COLOR=red]The prime "37*2^6xxxxx1-1" is unusually large. Primes this size require must be submitted manually by e-mailing [U]Chris Caldwell[/U] both the prime and an explanation how it was proven prime.[/COLOR][/QUOTE]Haven't seen this warning before. :rolleyes:
And maybe will never see again.

It has more than 2 million digits.

[QUOTE=Batalov;379353]Haven't seen this warning before. :rolleyes:
And maybe will never see again.

It has more than 2 million digits.[/QUOTE]

:bow:

Incredibly awesome!

Beautiful! Congrats Serge!

Thanks! Additional thanks to Dmitry "unconnected" Domanov who drove this base to 600k previously.

The proof code is new (credit to RPS files is due), but here's the direct link now:
37·2[SUP]6660841[/SUP]-1 ([URL="http://primes.utm.edu/primes/page.php?id=118270"]2,005,115 digits[/URL])

Congratulation Batalov. This means that base 1024 is now a 1 k remaining base. Did you know that you could see such a warning again, if you decide to prime k=29 for base 1024? :wink:

May I suggest that someone creates a MegaPrime list either here as a sub thread or as a subpage on the CRUS website... anyone who will be able to do such a list? :smile:

Take care

Kenneth

Brilliant find! Congratulations to Serge!

:groupwave:

[QUOTE=Batalov;379363]Thanks! Additional thanks to Dmitry "unconnected" Domanov who drove this base to 600k previously.

The proof code is new (credit to RPS files is due), but here's the direct link now:
37·2[SUP]6660841[/SUP]-1 ([URL="http://primes.utm.edu/primes/page.php?id=118270"]2,005,115 digits[/URL])[/QUOTE]

OUTSTANDING!! Way to go Serge! Also thank you to Dimtry for previous searching and for helping with the proof. It's interesting that it turned out to be just over 2M digits.

On an exciting side note, CRUS has now moved ahead of PSP into 5th place on the project scores list. Great work everyone!

:party::bounce wave::bow wave::groupwave::joe o::george:

[QUOTE=Batalov;379363]The proof code is new (credit to RPS files is due), but here's the direct link now:
37·2[SUP]6660841[/SUP]-1 ([URL="http://primes.utm.edu/primes/page.php?id=118270"]2,005,115 digits[/URL])[/QUOTE]

Congratulations on such a large find and a top 25 to boot. Job well done!

I noticed that this new proof code does not list the sieve effort, although it does list the sieve programs. This is not unique as there are hundreds of other primes that share the same phenomenon. What makes this submission different is that it credits a project for simply providing the file from the sieve effort. I'm interested to learn the reasoning for this decision. Shouldn't it only list CRUS?

[QUOTE=jmblazek;379657]... I'm interested to learn the reasoning for this decision. Shouldn't it only list CRUS?[/QUOTE]
"Ask not what your project can do for you, ask what you can do for your project," I think.

[URL="http://primes.utm.edu/bios/code.php?code=L426"]Cruelty[/URL], [URL="http://primes.utm.edu/bios/code.php?code=L3345"]unconnected[/URL], [URL="http://primes.utm.edu/bios/code.php?code=L1959"]amphoria[/URL], [URL="http://primes.utm.edu/bios/code.php?code=L2484"]Thomas11[/URL], and many others also apparently received [B]nothing[/B] from RPS (as you suggest), but they include it in their proof-code, don't they?

Why? Maybe for the same reason, maybe not. Why not ask them to remove RPS from their proof-codes just as well -- and hear their answers?

When Rieselprime will advance with k=29 and k=37, they will be able to use [URL="http://mersenneforum.org/showpost.php?p=368825&postcount=1777"]this data[/URL] and [URL="http://mersenneforum.org/showpost.php?p=379230&postcount=1837"]this data[/URL] to save a significant fraction of work.
On all powers of 2, CRUS and RPS have an overlap and a synergy; work is not done twice.

As for sieving, [URL="http://mersenneforum.org/showthread.php?t=19170"]based on my previous experience[/URL] with k=41 and k=243, I did sieve to the optimal depth and it was a fraction of total time.
Additional savings from using the 21P sieve file were an even smaller fraction.
The good news is that the sieve file seems fine now.

"...of course, that's just my opinion. I could be wrong." (c)

My apologies. I was not aware that you personally sieved that k. From your post it appeared that credit was being given to RPS for the file. So, if it's not for their sieve file, why still credit RPS? Is it because they "manage" k=37?

2172*117^180355+1 is prime

4k's left for S117.

I will post an update in a couple of weeks when I get to a round n.

Finally found a big one. From port 1400:

84363*2^2222321+1 is prime!

This is >50% larger than any prime that I have ever found. :bounce:

I just so happened to see this pop up on my main desktop machine. It has been proven prime but hasn't yet been reported to the server because it looks like it is checking to see if it is a GF factor of anything. It appears like that will take a couple of hours. I'm not exactly sure how that works.

[QUOTE=gd_barnes;385642]Finally found a big one. From port 1400:

84363*2^2222321+1 is prime!

This is >50% larger than any prime that I have ever found. :bounce:

I just so happened to see this pop up on my main desktop machine. It has been proven prime but hasn't yet been reported to the server because it looks like it is checking to see if it is a GF factor of anything. It appears like that will take a couple of hours. I'm not exactly sure how that works.[/QUOTE]

Congrats!

For base 2 Proth primes, the client will run pfgw to find GF factors then report them to the server. It could take a while since the GF testing is done across a number of bases. Any GFs found should be reported to Wilfred Keller.

[QUOTE=rogue;385661]Congrats!

For base 2 Proth primes, the client will run pfgw to find GF factors then report them to the server. It could take a while since the GF testing is done across a number of bases. Any GFs found should be reported to Wilfred Keller.[/QUOTE]

I let it run for more than 2 hours looking for GF factors. It finished at least one test but then came this, which I noticed about 15 minutes into its next testing:

GF_sprime_3: 84363*2^2222321+1 80000/222232020

:confused: :ermm: :huh: :surprised :surrender

222232020 (!!)...That is not a typo and is not an overlay of some printing on the screen. I don't know what it is trying to test but 222M+ iterations is not a test that I wish to complete. According to my calculations, it would have taken a month to complete it. I then hit CTL-C, it returned the prime to the server, and it requested another test like I had hoped.

Any thoughts?

[QUOTE=gd_barnes;385663]GF_sprime_3: 84363*2^2222321+1 80000/222232020

:confused: :ermm: :huh: :surprised :surrender

222232020 (!!)...That is not a typo and is [B]not an overlay of some printing on the screen[/B].[/QUOTE]

Are you sure? The "2020" looks suspicious, since 2222320 is so close to 2222321. I think this is all it is. This would put the test time at ~7 hours.

[I]Of course[/I] it is an overlay. The previous stage (dubbed "GF_sprime_2") left some digits on your screen.
GF_sprime_2
GF_sprime_3
GF_sprime_5 are run for the -go test
(GF_sprime_7
GF_sprime_11 are additionally run for the -gxo test)
Exercise patience.

If you have many cores, you can run
pfgw -f0 -gos2 -q"84363*2^2222321+1"
pfgw -f0 -gos3 -q"84363*2^2222321+1"
pfgw -f0 -gos5 -q"84363*2^2222321+1"
pfgw -f0 -gos6 -q"84363*2^2222321+1"
pfgw -f0 -gos10 -q"84363*2^2222321+1"
pfgw -f0 -gos12 -q"84363*2^2222321+1"
in parallel.
For a full -gxo test, you'd need 40 cores, so it is best to leave pfgw -f0 -gxo -q"84363*2^2222321+1" run separately for a few days.

[QUOTE=Batalov;385666][I]Of course[/I] it is an overlay. The previous stage (dubbed "GF_sprime_2") left some digits on your screen.
GF_sprime_2
GF_sprime_3
GF_sprime_5 are run for the -go test
(GF_sprime_7
GF_sprime_11 are additionally run for the -gxo test)
Exercise patience.

If you have many cores, you can run
pfgw -f0 -gos2 -q"84363*2^2222321+1"
pfgw -f0 -gos3 -q"84363*2^2222321+1"
pfgw -f0 -gos5 -q"84363*2^2222321+1"
pfgw -f0 -gos6 -q"84363*2^2222321+1"
pfgw -f0 -gos10 -q"84363*2^2222321+1"
pfgw -f0 -gos12 -q"84363*2^2222321+1"
in parallel.
For a full -gxo test, you'd need 40 cores, so it is best to leave pfgw -f0 -gxo -q"84363*2^2222321+1" run separately for a few days.[/QUOTE]

I see. OK makes sense. Wow. So it would have potentially run GF factoring for several hours/days on that one core before reporting the prime to the server while that k continued to be tested?! Not good.

I'll dedicate one core and run the [ pfgw -f0 -gxo -q"84363*2^2222321+1" ] command until it finishes.

One to report here:

155877*2^2273465-1 is prime

:cool:

[URL="http://primes.utm.edu/primes/page.php?id=118820"]1344 · 73^355570 + 1[/URL] is prime and proves S73.

[QUOTE=Batalov;388464][URL="http://primes.utm.edu/primes/page.php?id=118820"]1344 · 73^355570 + 1[/URL] is prime and proves S73.[/QUOTE]

Congrats!

:bounce wave:

Nice ck (1444) eliminated also. :smile::smile:

[URL="http://primes.utm.edu/primes/page.php?id=118828"]493 · 72^480933 + 1[/URL] is prime and proves S72.

[QUOTE=Batalov;388592][URL="http://primes.utm.edu/primes/page.php?id=118828"]493 · 72^480933 + 1[/URL] is prime and proves S72.[/QUOTE]

Double wow! Proof of consecutive bases within 2 days of each other. That has to be the best since the very early days of the project.

:banana::bounce:

[URL="http://primes.utm.edu/primes/page.php?id=118832"]6 · 258^212134 - 1[/URL] is prime; R258 is proven.

[QUOTE][URL="http://primes.utm.edu/primes/page.php?id=118832"]6 · 258^212134 - 1[/URL] is prime; R258 is proven. [/QUOTE]

Wow. That's one heck of a roll you are on Serge. Keep it up.

:smile::bump2::smile:

[QUOTE=Batalov;388624][URL="http://primes.utm.edu/primes/page.php?id=118832"]6 · 258^212134 - 1[/URL] is prime; R258 is proven.[/QUOTE]

:bounce::showoff::george:

Waaa... man! That's the spirit, haha.
Congrats!

S311
 

[URL="http://primes.utm.edu/primes/page.php?id=118836"]10 · 311^314806 + 1[/URL] is prime; S311 is proven.

[QUOTE=Batalov;388651][URL="http://primes.utm.edu/primes/page.php?id=118836"]10 · 311^314806 + 1[/URL] is prime; S311 is proven.[/QUOTE]

Congratulations! Did you recently stumble upon a secret stash of cores? :grin:

[QUOTE=Batalov;388651][URL="http://primes.utm.edu/primes/page.php?id=118836"]10 · 311^314806 + 1[/URL] is prime; S311 is proven.[/QUOTE]

Congrats again!! I think Serge has been hording primes. lol

[URL="http://primes.utm.edu/primes/page.php?id=118857"]2564 · 75^610753 + 1[/URL] is prime (1,145,203 digits); S75 is a "wanker".

[QUOTE=Batalov;388964][URL="http://primes.utm.edu/primes/page.php?id=118857"]2564 · 75^610753 + 1[/URL] is prime (1,145,203 digits); S75 is a "wanker".[/QUOTE]

Congrats again! A nice huge prime that comes in at #72 in the top-5000.

[URL="http://primes.utm.edu/primes/page.php?id=118912"]373 · 520^342177 + 1[/URL] is prime; S520 is a 1-ker (will continue to n=400k).

[URL="http://primes.utm.edu/primes/page.php?id=118930"]30 · 7^670289 + 1[/URL] (= 1470 · 343^223429 + 1) eliminates k=1470 from S343; S343 and R343 are 5-kers.

R28
 

[URL]http://primes.utm.edu/primes/page.php?id=118945[/URL]

6207*28^430803-1 is prime - R28 is now a 4ker

...blast!...
 

Just so that it is not as much a surprise to anyone ([I]as it was for me[/I]), --
I've got a huge pseudoprime (k=3072, b=81, Sierp.) and in a short time it will be rejected by the UTM server.

I submitted it after running a 16-thread 7-PRP test using mprime, but postmortem will probably show that I put that "PRPBase=7" option in the wrong file (prime.txt? local.txt? I probably remembered wrong into which one I was supposed to put it), and when it returned success, I submitted it to UTM before running the pfgw -t (which is in base 5).

I am running more tests, but it is likely a fluke. It is a very large 3-SPRP though.
___________________________

[COLOR="DarkGreen"]EDIT: Or maybe [URL="http://primes.utm.edu/primes/page.php?id=118946"]it is a prime[/URL], after all.[/COLOR]

Added [URL="http://primes.utm.edu/primes/page.php?id=119040"]119040[/URL] : 144*648^186106+1 (523254 digits)

Not the smallest but reprteable :)