Re: Mersenne: New Goal?
At 09:27 AM 9/1/99 -0400, you wrote: It is very likely that we will succed to reach the Y2K goal. Maybe it is time now to set a new one? I stick with the suggestion I made a few months ago: 10 000 000 before the new millenium? What do you think? I think we'll now endlessly debate whether the millennium begins at 12:00:01 on January 1st, 2000, or one year later than that. ;-) With roughly 71 CPU years a day, and linear growth to about 101 CPU years a day in 16 months (a SWAG), that's an average of 86 years per day, or 486.6 days.That's 41,800 CPU years between now and the first day of 2001. With only 14,944 years to go to clear those exponents less than 10.3MM, I'd say you stand a fair chance of succeeding, even though the inevitable last minute stragglers will take much longer than expected. (No, not the poaching thread again!). We stand a fair shake at getting those less than 11MM cleared. Now, if you thought that the Millennium begins on the first day of 2,000, well, then we'll only get about 8750 CPU years done between now and then, and will not likely have cleared all of those exponents. Have I re-opened enough old wounds (poaching, when is the millennium), or should I talk about overclocking and Island theory now? ;-) _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Several illegal sumout
Hi, At 05:17 PM 9/1/99 +0200, Dennis Jørgensen wrote: But in the test I'm running now I've had 4 of these errors (exponent just over 8 million). This seems a bit too much to me, am I right? Your result is likely OK. Prime95 recovers well from this error and it not usually an indicator that undetected errors are corrupting the results. The readme.txt file gives some ideas as to what the causes might be. I've noticed that they happen as the computer starts. This is new. The usual cause is a device driver playing a MIDI file. Probably a driver did not save the CPU state properly while initializing. With the 2 last errors I've also noticed that the tray icon appears later when the errors happen, Not unexpected. Prime95 sleeps for 5 minutes after a SUMOUT error. Celeron-400 gets 0.314 sec/interation on the exponent I'm running now, Seems right. Compare it to the PII-400 timings on http://www.mersenne.org/status.htm Remember that the timings on that page are for version 19 which is up to 10% faster than version 18. Regards, George _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Several illegal sumout
At 17:17 1999-09-01 +0200, Dennis Jørgensen wrote: My problem is that in the first 2 tests I've had one illegal sumout error in each (both exponents were around 7.6-7.7 million). As the readme text said this probably didn't mean anything I didn't do anything about it. But in the test I'm running now I've had 4 of these errors (exponent just over 8 million). This seems a bit too much to me, am I right? I don't think you should worry. It often happens, that after my younger brother have played some games on my (family's) fastest machine (a PII-233) I can immediately tell he have done so, because when I connect to Internet Prime95 reports a bunch of "illegal sumout", around 20 at the extreme, though usually only one or two. I hate when it happens, but as far as I know it haven't done any harm to my results. By the way, is anyone interested in a copy of p6972593 at the 690th iteration? I wasted a whole month during the summer to check it, and yes, it turned out to be prime, regardless of all the "illegal sumout"s the occured during the process! Regards, Johan Winge _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: too hot? too cold? perfect?
With every Mersenne number there is an associated perfect number, the sum of whose factors exactly equal the number. I discovered a fascinating thing today, for which I must introduce some new terminology. If a number is greater than the sum of its factors, let it be a cold number. If a number is less than the sum of its factors, let it be a hot number. Odd numbers are all cold, for instance, and the first hot number is 12. Nowthen, I found that the ratio of cold numbers to hot numbers is always about 3. Even when you get up to large numbers [I checked them all up to about 100,000] the ratio seems to stay right around 3 colds to every hot. Is there an embarrassingly trivial reason for this? Is there established terminology for hot and cold numbers? spike _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
