Mersenne Digest Thursday, September 6 2001 Volume 01 : Number 880 ---------------------------------------------------------------------- Date: Mon, 03 Sep 2001 22:27:36 From: "Alan Simpson" Subject: Re: Mersenne: M727 factored! hi Eric (and everyone else), I have what's probably a silly question. You wrote this: > M727 - 94.3716% probability - 2 factors > M727 - 52.8693% probability - 3 factors > M727 - 6.0014% probability - 4+ factors Why do these probabilities add up to more than 100%? > M751 - 83.8467% probability - 2 factors > M751 - 74.2974% probability - 3 factors > M751 - 19.5801% probability - 4+ factors ditto thanks, Alan Simpson _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 4 Sep 2001 10:26:55 -0400 From: Frank Solensky Subject: RE: Mersenne: M727 factored! > I have what's probably a silly question. > > You wrote this: > > M727 - 94.3716% probability - 2 factors > > M727 - 52.8693% probability - 3 factors > > M727 - 6.0014% probability - 4+ factors I assumed it was that they aren't mutually exclusive -- "2 factors" should have been "2+ factors" instead. _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 04 Sep 2001 18:28:53 +0200 From: Alexander Kruppa Subject: Re: Mersenne: M727 factored! Frank Solensky wrote: > > > I have what's probably a silly question. > > > > You wrote this: > > > M727 - 94.3716% probability - 2 factors > > > M727 - 52.8693% probability - 3 factors > > > M727 - 6.0014% probability - 4+ factors > > I assumed it was that they aren't mutually exclusive -- "2 factors" should > have been "2+ factors" instead. Thats what I first thought, but then 2+ factors should have been 100% as we knew that M727 is not prime. Alex _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 04 Sep 2001 18:05:48 From: "Alan Simpson" Subject: RE: Mersenne: M727 factored! hi Frank, thanks for the message. That makes more sense. The only problem with your interpretation is that we know M727 is composite, so shouldn't the "2 factors" probability be 100%? >I assumed it was that they aren't mutually exclusive -- "2 factors" should >have been "2+ factors" instead. > Alan _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 4 Sep 2001 20:10:18 +0100 From: "Daran" Subject: Re: Mersenne: M727 factored! - -----Original Message----- From: Alexander Kruppa To: Frank Solensky ; mersenne@base.com Date: 04 September 2001 17:48 Subject: Re: Mersenne: M727 factored! >Frank Solensky wrote: >> >> > I have what's probably a silly question. >> > >> > You wrote this: >> > > M727 - 94.3716% probability - 2 factors >> > > M727 - 52.8693% probability - 3 factors >> > > M727 - 6.0014% probability - 4+ factors >> >> I assumed it was that they aren't mutually exclusive -- "2 factors" should >> have been "2+ factors" instead. > >Thats what I first thought, but then 2+ factors should have been 100% as >we knew that M727 is not prime. All of the probabilities are either 0% or 100%, so I would guess that these are probabilities calculated on some heuristic basis which did not take the result of the LL test into account. Presumably we can multiply each of the above by 100/94.3716 to incorporate this additional information. >Alex Daran G. _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 04 Sep 2001 18:57:50 -0400 From: George Woltman Subject: Mersenne: NT / 2000 / XP users Hi all, I've just discovered a free utility that lets you run prime95 as a service under the above operating systems. The good news is you will now have access to prime95's user interface to monitor progress! To try it, follow the instructions at http://www.mersenne.org/freesoft.htm They are near the v20 download info, but it will work for v21 too. Have fun, George _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 04 Sep 2001 19:41:16 -0400 From: Bruce A Metcalf Subject: Re: Mersenne: NT / 2000 / XP users At 06:57 PM 04-09-01 -0400, George Woltman wrote: > I've just discovered a free utility that lets you run prime95 as >a service under the above operating systems. The good news is you >will now have access to prime95's user interface to monitor progress! > > To try it, follow the instructions at http://www.mersenne.org/freesoft.htm >They are near the v20 download info, but it will work for v21 too. Hi, it's me, the anti-geek again. Can someone explain to me why (and if) it's better to run Prime95 as a service under these OSs? Is there a speed advantage? Also, who would be serving whom? Referrals to relevant FAQs will also be appreciated. _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 04 Sep 2001 20:18:35 -0400 From: George Woltman Subject: Re: Mersenne: NT / 2000 / XP users Hey, At 07:41 PM 9/4/2001 -0400, Bruce A Metcalf wrote: >Can someone explain to me why (and if) it's better to run Prime95 as a >service under these OSs? Is there a speed advantage? Also, who would be >serving whom? There is no speed advantage. There are only 2 advantages that I see: 1) If you logoff of Windows when you are not using your computer, prime95 will continue to run as a service, it will exit during logoff if it is not installed as a service. Many businesses want you to logoff your computer for security reasons. Most home users don't logoff because security is not an issue. 2) If you install prime95 as a service it will start running at bootup before anyone logs on. If a power failure hits at night, prime95 will restart automatically assuming your computer restarts when power is restored. Hope that helps, George _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 04 Sep 2001 20:25:24 -0400 From: Jeff Woods Subject: Re: Mersenne: NT / 2000 / XP users At 07:41 PM 9/4/01 -0400, you wrote: >Can someone explain to me why (and if) it's better to run Prime95 as a >service under these OSs? Is there a speed advantage? Also, who would be >serving whom? The primary advantage is that it remains running regardless of who (if anyone) is actually logged onto the box. Much in the same "general concept" of how mprime runs on Linux in the background of the context of the user ID that started it, mprime continues to run until killed, even if the user that started mprime logs off the Linux box. NT services are the same -- they AUTOMATICALLY start (if so configured) at bootup, and automatically start up in the context of a specific user (i.e. an auto-cron job on a Linux box, a user's start.start file), and runs until stopped, no matter who logs in or out of the machine. This can be of great benefit to those NT boxen that may be rebooted -- it's the only way to auto-start an application in that manner, without hacking the registry to automatically log a user onto the box, and that presents a security hole to fly the space shuttle through..... _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 4 Sep 2001 20:05:02 -0700 From: "Aaron Blosser" Subject: Re: Mersenne: NT / 2000 / XP users Of course, I use the NT service version of Prime which installs itself as a service. Of course, as George mentioned, you don't get the nice user interface, but considering I run it on a bunch of "lights out" machines, I could care less about the interface. :) Plus, sometimes George doesn't get the NT service version out as soon as the Prime95 versions. :) - ----- Original Message ----- From: "Jeff Woods" To: Sent: Tuesday, September 04, 2001 5:25 PM Subject: Re: Mersenne: NT / 2000 / XP users > At 07:41 PM 9/4/01 -0400, you wrote: > > >Can someone explain to me why (and if) it's better to run Prime95 as a > >service under these OSs? Is there a speed advantage? Also, who would be > >serving whom? > > The primary advantage is that it remains running regardless of who (if > anyone) is actually logged onto the box. Much in the same "general > concept" of how mprime runs on Linux in the background of the context of > the user ID that started it, mprime continues to run until killed, even if > the user that started mprime logs off the Linux box. NT services are the > same -- they AUTOMATICALLY start (if so configured) at bootup, and > automatically start up in the context of a specific user (i.e. an auto-cron > job on a Linux box, a user's start.start file), and runs until stopped, no > matter who logs in or out of the machine. > > This can be of great benefit to those NT boxen that may be rebooted -- it's > the only way to auto-start an application in that manner, without hacking > the registry to automatically log a user onto the box, and that presents a > security hole to fly the space shuttle through..... > _________________________________________________________________________ > Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm > Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 04 Sep 2001 23:32:39 -0400 From: George Woltman Subject: Mersenne: V21.2 beta bug Hi all, A relatively rare bug has been found in the version 21.2 beta. Only P4 users are affected. If you do not own a P4 you can now delete this message. From the whatsnew.txt: A bug was fixed in the error recovery code. After getting a "Disregard last error" message, the user was treated to a new error on every iteration. The end result was incorrect. The bug only affected the error recovery of the new P4 FFT introduced in the beta version 21.2. What should you do if you are running v21.2 on a P4? If you've run into the long string of errors after a "disregard last error" message in results.txt (about three people have reported such symptoms), then restart the test from scratch or from a save file created before the error. You can also rest easier - your machine probably does not have hardware errors. If you haven't had the error, then consider copying the pNNNNNNN save file once each day until I can upload a fix in version 21.3. Many thanks to the beta test victims - that's why we have beta testers! Have fun, George _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 05 Sep 2001 15:56:43 -0400 From: George Woltman Subject: Mersenne: P4, Redhat 7.1, and version 21 Hi, Has anyone gotten this combination to work? I just had a bug report that mprime is crashing if the CPU type is set to P4. I'd rather solve this without having to install Redhat on my own P4. It is my primary machine and backing up and repartitioning must be done with great care. Thanks, George _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 6 Sep 2001 18:18:31 +0100 From: "Daran" Subject: Re: Mersenne: M727 factored! Eric Hahn wrote: > M727 - 94.3716% probability - 2 factors > M727 - 52.8693% probability - 3 factors > M727 - 6.0014% probability - 4+ factors > M727 - 91.1834% probability - 313-bit min. factor size > M727 - 93.0447% probability - 428-bit max. factor size It's impossible for these to be both true, since their product would then have 741 bits. > M727 - 21.7336% probability - highly composite factors What does this mean? > M751 - 83.8467% probability - 2 factors > M751 - 74.2974% probability - 3 factors > M751 - 19.5801% probability - 4+ factors > M751 - 87.2999% probability - 281-bit min. factor size > M751 - 81.0003% probability - 526-bit max. factor size Ditto 807 bits. > M751 - 30.1716% probability - highly composite factors Is M751 now the smallest unfactorised composite Mersenne? What is the smallest Mersenne not completely factorised? Regards Daran G. _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ End of Mersenne Digest V1 #880 ******************************