Mersenne: Expected completion date
Hi. I just finished my first LL test. I know I shouldn't broadcast this to the list, but I couldn't resist; so, here goes... M8180017 is NOT prime!!! ;) Now, back to reality... At 8178600th iteration I checked the status window, and it showed that Prime95 will be working on this for the next 5 hrs 25 mins... So I took my calculator, and asked him: (8180017-8178600)*0.430=? He said something about his aching buttons, but finally answered: 609,31 So, it seemed like 10 mins 10 secs later I will be given the naked truth about M8180017. That's like 5 hrs 14 mins 50 secs earlier than Prime95 thought... But when I restarted Prime95, it showed the right end-time (10 mins). So, my guess is, this calculations are based on some data saved when Prime95 closes - could those data be saved every time the status window is opened? That would lead to the right calculations, right? Thanks for your time, -- Shot PS: On second thought - maybe it was because Prime95 was told it will be running 18 hrs/day, and it was 24 hrs/day? __ c"? Shot - [EMAIL PROTECTED] hobbies: Star Wars, Pterry, GIMPS, ASCII `-' [EMAIL PROTECTED] join the GIMPS @ http://www.mersenne.org Science Explained (by Kids): Cyanide is so poisonous that one drop of it on a dogs tongue will kill the strongest man. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: M(M(127)) and other M(M(p))
Hi, I just tried a quick run of Georges new P-1 code on M(M(17)), and lo! [cut] At prime 499549. Time thusfar 1707.604 sec. (341520836670 clocks) Stage 1 complete. 365804 transforms. Time: 1717.294 sec. (343458751180 clocks) Stage 1 GCD complete. Time: 19.737 sec. (3947333454 clocks) M131071 has a factor: 14899621191992882743 That wan't hard. But one thing puzzles me: P-1 = 2*3*61*6229*131071*49861943 The factor was found after stage 1 with a limit of 50 - how can it find a factor which is 1 mod (49861943) ? Another magic trick by George? Ciao, Alex. I checked Chris Caldwell's pages on this, and Curt Noll's trial-factored M(M(127)) to 5.10^50, surprisingly low considering the size of M(127) itself, I noticed many other M(M(p)) as listed in http://www.garlic.com/~wedgingt/MMPstats.txt have only been tested to very low limits indeed. I wondered why there wasn't more work done on these - though I understand it's very hard to motivate people when Guy's law of small numbers no doubt applies, but everything M(M(61)) and above is currently unknown. It would be nice to see a few more results there. Chris _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: complaint
Greetings again, Thank you for your responses and stuff. I am de-confused. I understand the relationship between the gimps and entropia.com, pretty much. After upgrading to the latest mprime, the segfault problems are gone. (segfault due to less than 16MBs of RAM, and segfault after goign to Options/ CPU in the preferences don't happen anymore.) Yes, I was worried about being polite when I wrote my e-mail, because I was annoyed and wasn't sure how I was going to sound. Thanks for the SysV init script, I was trying to write one of those, but I don't know how :) That's how I ended up running two or three copies of mprime in the first place. (Start worked, stop didn't.) Now try this, make a temporary directory, copy all your ordinary mprime files into it. Do something like this: ./mprime ./mprime ./mprime wait...ten seconds then run something likes this: killall mprime (making sure that you don't kill the one you want to keep running) I find that my p## file is gone! TomG PGP signature
Re: Mersenne: Factor of 2^(2^31-1)-1 found ($)
All (and especially Chris), Yesterday (and the day before), I went to the Illinois number theory conference. There (2nd talk of yesterday) J. P. Selfridge announced that he would give away $1000 US for any factor found of a number which ought to be prime (he provided a list). On that list was 2^(2^31-1)-1. Please post the list of candidates, to the mailing list. Ken F_m for m=14,20,22,24,31 M(M(p)) for p=31,61,127 M(B(p)) for p=31,61,127 F_m for m=2^k+k k=6 B(p)=(2^p+1)/3 -Lucas _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Expected completion date
Hi, At 12:33 PM 9/20/99 +0200, Shot wrote: At 8178600th iteration I checked the status window, and it showed that Prime95 will be working on this for the next 5 hrs 25 mins... So, it seemed like 10 mins 10 secs later I will be given the naked truth about M8180017. That's like 5 hrs 14 mins 50 secs earlier than Prime95 thought... Prime95 updates this information on a program restart (as you found out) and every 65536 iterations. I've fixed it to update this every 128 iterations. The 18 vs. 24 hours a day info will cause the estimate to be off by 25% as prime95 assumes the 6 off hours are distributed uniformly throughout the day. Keep those bug reports coming, George _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
RE: Mersenne: GIMPS client output
Rick, Glad to see *somebody's* awake!! grin From: Eric Hahn P.S. At the 79.3M range, you'll probably not want to set it at 100 iterations... Per iteration time on 266MHz PII with 64MB RAM is 58.781 seconds!!! The only question that comes to mind is if you had to plough through factoring before you got to the LL test...but then I realise that you still wouldn't be done if that were true. You're right! Even on a P3-500, it'd take 7-8 months to plough through all the factors to 2^72. I intentionally told it that it had been factored thru 2^73 to prevent it from doing such. This was for a test I was running... I signed up for an exponent in the 33mil range and the factoring alone took 13 days on a P3-500. I'd originally does it for testing purposes, but after that I've just got to let it continue. :-) I've got 2 machines working on 10M digit exponents. One will work until completion, while the other will be forced to trial-factor only (a feature not offered in v19 which I've mentioned to George). In a year's time, I'd love to see some numbers on how many signed up for tem million digit numbers and later quit for smaller exponents... Well, let's see... You got yours assigned Sept. 5 at 3:38 UTC. 14 exponents assigned, 3 factored, 11 still in progress... and counting... Interesting to note, however, that 2 of the exponents factored and 1 still in progess had factors listed on Alex Kruppa's site: http://www.informatik.tu-muenchen.de/~kruppa/M33M/index.html before 10M digit exponents were assigned by IPS. Which ones?? 33,219,341 and 33,219,469 and 33,219,707 (33,219,341 was assigned by IPS to Alex, BTW g) Eric Hahn _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Prime95 v19 oops...
Something I forgot from earlier playing, the manual factoring savefiles on Prime95 v19 at least don't work out too well especially on dual-CPU machines... Since these savefiles will always be named "p000" regardless of the -A parameter and exponent to test ;) It isn't the first time I've suddenly found both CPU's crunching away on the same factoring assignment... Oh well. -Donwulff _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Important info on M(M(p)) from Wilfrid Keller
-- Forwarded message -- Date: Mon, 20 Sep 1999 19:55:53 +0200 (DFT) From: Wilfrid Keller [EMAIL PROTECTED] To: [EMAIL PROTECTED] September 20, 1999 Dear Warut, Dear Colleagues: Concerning the subject of Mersenne numbers M(q) = 2^q - 1, where q = 2^p - 1 itself is a Mersenne prime, I am sorry I hadn't seen your relevant web page before. As the factor of M(M(13)) that I had found in 1976 might suggest, I have shown interest in this particular kind of Mersenne numbers since many, many years. Re- garding the factor of M(M(31)) just rediscovered by Lucas Wiman, I regret to inform you that it was already "published" in 1983. Unfortunately, Guy Haworth's notes (please see the references be- low) were released only "privately", but were in fact widely cir- culated. The second prime factor of M(M(31)), found by Tony Forbes, was also known to me for some years (again, see below). Let me take this opportunity to communicate to you the complete records of my search for factors of numbers M(M(p)), particular- ly including the attained limits, which may help to avoid further duplication. Also, please note that M(M(127)) was shown to have no factor 2h x M(127) + 1 for h 6.8 x 10^8. If you should find it of interest to forward my data to some per- tinent mailing list (NMBRTHRY or so), please feel free to do so. And if you have any questions related to this topic, I would be glad to respond. With my best wishes to all of you, Wilfrid Keller [PS: This note is by no means intended to earn the money allegedly offered for a proof that M(M(31)) is not a prime. Anyway, the reward would have been for discovering a factor, and not for giving a reference where to look it up, I suppose.] Known prime factors 2h*M(p) + 1 of "iterated" Mersenne numbers M(M(p)) as of November 1996 ph DiscovererReferences 1320644229Keller Haworth [1983], Ribenboim [1988] 17 884RobinsonRobinson [1957] 17 245273Keller Haworth [1983] 19 60RobinsonRobinson [1957] 19 5480769Keller Found Aug 20, 1994 (unpublished) 31 68745Keller Haworth [1983] 3120269004Keller Found Aug 28, 1994 (unpublished) References -- Raphael M. Robinson, Some factorizations of numbers of the form 2^n +/- 1, MTAC (Math. Comp.) 11 (1957), 265-268. Guy Haworth, Mersenne Numbers, Reading, Berkshire, 1983 (privately published notes), and subsequent updates. quoted as reference #203 in Daniel Shanks, Solved and Unsolved Problems in Number Theory, 3rd ed., Chelsea, New York 1985, and as reference #223 in John Brillhart, D.H. Lehmer, J.L. Selfridge, Bryant Tuckerman, and S.S. Wagstaff, Jr., Factorizations of b = 2, 3, 5, 6, 7, 10, 11, 12 up to high powers, 2nd ed., American Mathematical Society, Providence, Rhode Island, 1988. Paulo Ribenboim, The Book of Prime Number Records, Springer, New York 1988, p. 80. Search limits h L(p) for factors of "iterated" Mersenne numbers M(M(p)) as of November 1996 pL(p) 13 6.7 x 10^8 17 3.3 x 10^8 19 4.0 x 10^8 31 3.1 x 10^8 61 7.5 x 10^8 89 5.3 x 10^8 107 5.2 x 10^8 127 6.8 x 10^8 521 3.6 x 10^5 607 3.4 x 10^5 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Timing(?) errors
On Mon, Sep 20, 1999 at 09:49:51AM -0500, Willmore, David wrote: Not really much you can do. The way windows hands out memory almost guarentees TLB and L2 cache thrashing. Yeah, but some of the same problems are present when it comes to Linux... Perhaps I should go back to ReCache... Perhaps as a cron job? `Flush the darn caches every hour -- this ain't no fileserver' :-) Unless the code can look up the physical address where it's data is stored and ensure the correct alignment, there's not much that can be done--in a controled fashon. I didn't think the alignment was a problem? And would looking up the real, physical address be any easier in Linux? (The code could run with root access, if neccessary...) But perhaps you don't know anything about Linux at all, and I'm just throwing out questions in the wild... Guess a cc to [EMAIL PROTECTED] is in order. (Thanks to all you replyers, BTW.) Good weekend? If you asked if I had a good weekend, the answer was yes, I had. Thank you very much :-) (Now only one more week, and we'll have a week's vacation. Sometimes, going to school is not that stupid...) /* Steinar */ -- Homepage: http://members.xoom.com/sneeze/ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Interesting PrimeNet Error
Ah, here's something interesting... I was working on a machine which was running Prime95 (v18, BTW, and in a visible window), when it decided to contact PrimeNet. No Problem! It sent the text messages about trial-factoring until: [...] Sending text message to server: M10461667 has a factor: 7841028322998353783 Sending expected completion date for M10461667: Sep 21 1998 ERROR 11: Exponent already tested. [...] Yes, the expected completion date message was expected as the machine was still testing (for smaller factors), and was sitting at 127520*2^32 (Pass 5 of 16) at the time it did this... I just found it interesting that PrimeNet would produce an error like this. What would happen if Prime95 should happen to find a smaller factor? Would it be accepted? H. Eric Hahn _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Iteration Times (was: GIMPS client output)
Okay, okay... obviously a lot of people were awake sigh (you can stop flooding me with emails!!) In a previous message I wrote: P.S. At the 79.3M range, you'll probably not want to set it at 100 iterations... Per iteration time on 266MHz PII with 64MB RAM is 58.781 seconds!!! (Yes, it's true, but I'm also just checking to see if anybody's awake :)) I went back to the exponent in question and ran another test. There are a couple of notes here: 1) This originally was done for a particular test in QA. 2) George didn't have the new timings up at the time. 3) I thought it was high myself, but what did I know? What I found was: 1) I obviously had something running in the background I was not aware of. 2) The actual time dropped to 4.231 sec/iter 3) Amazingly, there didn't appear to be much HDD paging happening except went you hit 'STOP'! BTW, for those of you who don't know (or actually asked), these exponents use 4096K FFT runlengths, and 16M save files... Eric Hahn _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
