Re: Mersenne: Is there any life here?
Wow, are you kidding? I thought we'd had a pretty active last couple of weeks. A decent thread on security, and a few math questions. Of course, I could be getting my lists crossed again. :-( ---Chip On Mon, 16 Apr 2001 [EMAIL PROTECTED] wrote: > NO Mail lately, just wanted to know if the list is > active! > > - > This message was sent using GSWeb Mail Services. > http://www.gasou.edu/gsumail > > > _ > Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm > Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers > \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | www.chiplynch.com | (202) 904-8570(cell) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: GIMPS slowdown due to California power problems?
Well, I know it cost me a solid couple of days processing time for GIMPS.
My apartment was apparently blacked out briefly while I was at work, and
I've been turning my computers off in the evening to conserve, when
normally they'd be on.
The blackouts themselves have been brief, but they have happened. I'm in
San Francisco, although most of the reports I've heard have been from just
outside the bay area.
---Chip
On Mon, 22 Jan 2001 [EMAIL PROTECTED] wrote:
> I live in Southern California, and no blackouts have come out, yet.
> Everyone's been reporting that the main problem is in Northern California,
> San Francisco especially. San Diego Area has a good amount of power plants.
> Still, the people in California should, for the sake of fellow Californians,
> turn off their computers at 6pm, and turn them on at night shortly after the
> main usage time is over, 10pm. That is peak usage time, and we really don't
> want to use electricity at that time. That's also when rolling blackouts are
> issued. This summer, rolling blackouts could begin at the 6am - 8am period,
> a smaller spike that occurs.
>
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Re: Mersenne: Facelift (round 2)
I'm a bit late, but count my vote for the new page, but without frames.
Very few ofthe hugely populated sites on the web use frames, and there's
bound to be a reason.
A few more comments:
> 1) I dumped the mouse rollover and replaced the 44 different menu
> gifs with one navbar gif. This should help our European friends
> suffering from slow load times due to downloading separate gif files.
Keen. But this makes navigation tough for people who turn off images (or
use lynx)... with separate images, each image's alt tag becomes a link.
With an imagemap, it's customary I think to put a navigation list at the
top or bottom of the page, normally delimited by pipes ("|") of the
options... I don't see anything like that on this page, but I'm not using
a text browser, so I may be confused.
> 2) The text now wraps around the navbar. Some found the white space
> below the navbar ugly. I'm not convinced this is any better.
Count my vote for the old way, but it's not a real strong vote. I guess
we use space better with the wrapping on. Both look acceptable.
> 3) The status table should display OK in netscape.
>
> 4) The MSIE improperly terminated string bug is not fixed. I actually
> think its a bug in MSIE.
Examining the source, there are three offending lines in the source code:
src="http://js1.hitbox.com/js?acct=WQ50041406EA90EN0&m=w147&n=Main+Page
">
x2=" 5) I added alt tags to all entries.
>
> 6) The icons at the bottom of prime.htm are in a neat little row - thanks
> to someone that suggested putting them in a table.
>
> Here are the big open issues. I've not decided how to resolve them.
>
> 1) I really wanted the menu to stay fixed in a frame (I like being able
> to navigate anywhere in the site with one click and no scrolling), but
> sentiment against frames is quite strong. Also the current navbar doesn't
> fit in all screens (its 623 pixels high). I could offer a frames, non-frames,
> and text-only versions without too much trouble.
Consider making the NAV Bar smaller. Maybe decrease the font on the blue
links by a couple of points. You coul also put Marin's head to the right
of the banners instead of on the left, which would gie you a bit of space.
I agree with the anti-frames sentiment, tho. I have no real objections to
multiple pages, but people generally stick with what they're given unless
compelled not to, and it's a bit more aministration. Still, it's an
option.
> 2) The status and benchmark pages - the most difficult to convert to the
> new style - now have trouble fitting in the browser window. I can try smaller
> fonts or add enough text above the tables so that they appear below the
> navbar.
I'm sure there's a way to force them beneath the NAV bar, but I can't
think of it... used to have this sort of problem all the time. Have you
tried an or a solid tag? I'm rnning out of time to
experiment myself.
> 3) A redesigned banner at the top of every page. Many others have
> remarked how they too are poor graphic artists!
Can't help you here. I like the colors in the tables, and the look of the
NAV Bar. The Entropia banners look good (which they would, I guess since
the people claiming not to be graphic artists didn't make them!)... what
about putting arin's head on the right side of the GIMPS banner, in the
same way that 2^P-1 is on the left side... that could fix the NAV Bar
height problem, and maybe make the banner more attractive at the same
time.
> 4) And, of course, organizing the content! Along with displaying it
> in pleasing fonts and colors on a compatible background.
Can't help you there at all; knowing where everything is from vieweing it
all the time makes rethinking that kinda tough.
> The latest incarnations can be viewed at:
>
> http://www.mersenne.org/newhtml/prime.htm
> and
> http://www.mersenne.org/newhtml/status.htm
> and
> http://www.mersenne.org/newhtml/bench.htm
>
> More comments are of course welcome!
>
> Thanks again,
> George
Keep up the good work; Everything really looks great,
---Chip
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Re: Mersenne: pi
On Fri, 11 Feb 2000 [EMAIL PROTECTED] wrote: > It is my understanding that this list is for the promotion of the search > for mersenne primes. I may be a laymen when it comes to mathematics, but to > my knowlege, this is not a requirement of the list. ... > I would hope that your opinion is in the minority. It smacks of elitieism. Ouch. Sorry, there. Perhaps I misspoke; I was certainly misunderstood. I applaud anyone who is interested in math, and this mailing list is certainly full of such people. We often have good conversations here about all sorts of topics related to math, pi, infinities, whatever; last I recall we have Math PHD's and, well, cabinetmakers on the list and anyone in between. All welcome, and while it's not my place to do so, I encourage people to post; the archives are rich with posts on every topic and at every level of math. My apologies, anyway, if I sounded off the mark. I meant no ill will, and I believe I mentioned how enthusiastic I was about the thread. I just thought there may be better resources than here for certain discussions. Not so much that they don't belong here than that your questions may well be better answered somewhere else. I was, unbelievably, trying to be helpful. Anyway, sorry again. It shan't happen again. ---Chip \\ ^ // (o o) ---oOO--(_)--OOo-------- | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: pi
> >> Infinite to me means never ending. A precisely defined value to me is a > >> finite value. > > > > Your definition of infinite is not correct. > > Just glanced at my Websters Dictionary. infinite: 1. lacking limits; endless. > Endless and never ending seem synonymous to me. > What dictionary are you using? > > >> A never ending value is not finite. > > > > Pi is greater than 3 and less than 4, therefore it is finite. I don't mind people using their own definitions of words; it's a shortcoming of mathematics that fundamentally needs improvement. However, once definitions are agreed upon, they must be at least internally consistent. If you take finite and infinite to be exact opposites, then we can't discuss the magnitude of pi (the fact that it is greater than three and less than four) to mean its "finite"ness, and it's length in decimal digits to mean its "infinite"ness. If we did, it could be both finite and infinite at the same time which is apocryful if those are opposites. Language, NOT Mathematics, is (precisely) why these discussions are problematic. If you've ever read original works by Archimedes, Euclid, and others who try to define mathematics with a common language, you understand the frustration. While I think the topic is stimulating and important, the Mersenne list probably isn't the best medium for it, unfortunately. Anyone recommend a few good links on the subject? (Pi, The Language of Mathematics, any of that) ---Chip \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
RE: Mersenne: Comparitive bench, please?
My 233 is running much better than your 1.788 as well. A few million things come to mind... First, are you running the newest software? Prime95 is up to, what... 19.0.2? Something like that... I'm sure it's on the page. Also, if you're in a Microsoft environment, Richard's right... check for things in the Task Manager. "FindFast" is a Microsoft program that likes to eat CPU time, and can be removed from the "StartUp" folder if it's on your system. On the more obscure side of things, I just upgraded my motherboard, and had to do a lot of manual settings to get it to work 'efficiently' with my 233. A 233 is running a 66Mhz clock at a 3.5 multiplier rate... the motherboard I got (an Iwill motherboard) defaulted to something else, and it wasn't readily obvious that this was the problem. (Okay, it was readily obvious if you read the manual, but come on, who does that?). I/O isn't an issue with this software, but you may want to check your cache (L1 and L2), perhaps by disabling/enabling it in the bios to see how that affects performance, and you may want to download some benchmark programs (ZDNet has some good ones, I believe) to check your cache and Ram speeds. Generally those are the problems I find causing software to run poorly. ---Chip On Tue, 7 Dec 1999, Pardoe, Richard (PRDR) wrote: > I have a Pentium 232 running NT 4.0 with only 96 MB of RAM that is getting > about 0.6 seconds per iteration for an exponent in the 8,490,000 range. > > It might be worthwhile to look in the Task Manager to see what is using the > CPU time. My CPU is typically mid-90% of the time w/ Prime95. > > Rich > > -Original Message- > From: Jeff Woods > > I have a P-II/233 running NT 4.0 that I think is severely > underperforming. It has 256 MB of RAM, and much of it remains free. > ... > It is taking 1.788 seconds per iteration for exponents in the 8,290,000 > range. > > > _ > Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm > Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers > \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Quiet list?
Of course, we've got a classic chaotic feedback mechanism in place... if
the list is too quiet (posts per unit time is low), a thread will
spontaneously create itself to discuss the fact, immediately rendering the
list less quiet (increasing the post per unit time).
The normal traffic (e-mails not related to the lack of e-mails) could be
chaotic, but over the long haul is inexorably linked (I'd wager) to the
distributions of mersenne primes. That is, if you were to align the
graphs of mailing list traffic by time next to our progress towards
finding mersenne primes by time, you'd see huge influxes of traffic when
we found another prime (and probably when someone else finds one). That
sort of predictable dependance (fight about how predictable mersenne
primes are later) on an outside 'force' makes that sort of traffic
non-chaotic... right?
Alright, it's been a while... I haven't messed with Chaos theory since
those nice julia set posters were first starting to be pretty. But still;
it's something to ponder.
---Chip
On Fri, 19 Nov 1999, Spike Jones wrote:
> [EMAIL PROTECTED] wrote:
>
> > Why is the list so abnormally quiet? Is everyone vacationing?
>
> Ive been reading up on chaos theory to see if we can predict
> patterns in the number of postings. This looks like a classic
> application of choas theory. Is anyone here up to speed on
> that? I have four chat groups. The total number of posts
> I receive each day is far more predictable than the number
> of posts on GIMPS. Predictably. {8^D spike
>
> _
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>
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Re: Mersenne: Re: Schlagobers, Louisville style
On Fri, 22 Oct 1999, Jud McCranie wrote: > At 11:47 PM 10/21/99 -0400, Chip Lynch wrote: > > There's no reason for it to be COMPLETELY random. Plenty of trancendental > >numbers have easy to view patterns > > > Only an infinitesimally small % of them have patterns. For each one that > has a pattern there are an infinite number that don't. Of course! But by 'Plenty', I only meant an infinite number, which as you've pointed out on the whole isn't that much at all. *evil grin* ---Chip \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Re: Schlagobers, Louisville style
On Thu, 21 Oct 1999 [EMAIL PROTECTED] wrote: > I used to have a girlfriend from Louisville (Kentucky), but must admit > that I've forgotten her number... > > Seriously, I think you mean "Liouville" numbers. I thought that sounded odd. I myself am from Louisville (and if you find your girlfriend's number, I'll be glad to look for patterns in it)... Speaking of which... > But while watching the movie Pi, it occurred to me that since the number > Pi has *nothing* to do with base 10, there would be no repitition in the > digits in any approximation of it in base 10 (or any other integer base, > for that matter). The sequence of digits *should* be completely random, > and it's goofy for people to try to look for patterns. I mean hey, if > it's what you gotta do, go for it, but I think time would be better > spent on other things. There's no reason for it to be COMPLETELY random. Plenty of trancendental numbers have easy to view patterns (aka the Liouville numbers above)... Or eaiser, a number like .10100100011 (...) which also happens to be easily describable, but only noticeable in certain bases (this probably looks stupid in base 3, but I haven't the desire to find out right now). I remember some notes on interesting patterns in Pi that led one to believe that certain statistical events were NOT ocurring. For example, in a completely random set of (base 10) digits, one would expect a string of, say, 100 of the SAME digit to appear in the first so many digits of the number, however this doesn't happen in Pi and, furthermore, certain digits appear in large clusters more often than others in the list of 'known' digits. Does anyone have any stats on this? Personally, I imagine this is the same sort of statistical dribble as "The Bible Code", and someone probably got their Chi-squareds mixed up when they were doing the math, but since I'm not strong in statistics, it would be nice to hear an 'Expert' opinion. ---Chip \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Re: The Mysterious Ways of Mersenne primes
On Wed, 20 Oct 1999, Brian J. Beesley wrote: > I thought the legal value of pi was 4, in Indiana. Actually the > timber trade still calculates the volume of logs in an absurd way > which implies that pi = 4. I've seen this discussion before... if I recall, their estimation of PI was better for their purposes... the absurdity would be assuming that trees are perfect cylinders. ;-) > > But then, define random! If I toss a (`fair') coin, I'd say that it's > > random. However, a very quick viewer (or a computer) might see the moment > > before the coin hits the ground (and stays there), what it will turn up > > as. In other words, then the randomness is _not present_ at that time. > > Now, if you go backwards, you can probably calculate (if you're VERY > > quick -- remember this is all theoretical) this earlier on, perhaps all > > the way back to when the coin leaves your hand. Who knows, perhaps even > > further? :-) Ah, this has the ring of Schroedinger to it... The apparatus required to measure the flip of a coin that precisely early on may just have to interfere with the results. ?? Air density, air flow, speed, direction, and position in three dimensions... Brings a tear to one's eye. ---Chip \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Compaq dumps NT-on-Alpha
This confuses me... slashdot carried this story in the last 48 hours (at least I think it was them; I can't find the link now), but I thought it was very clear that CompaQ was dropping only the 32-Bit Windows dvelopment from Alpha, and KEEPING 64-Bit. The CNN story definitely leads you to believe that ALL NT support is being dropped. As much as I applaud forcing Microsoft to evolve by threatening them with rival operating systems, I can't imagine Compaq could completely drop NT support from the Alpha and not lost major revenue. Anyone closer to this know the story? ---Chip On Wed, 25 Aug 1999 [EMAIL PROTECTED] wrote: > Check out > > www.cnn.com/tech/computing/9908/24/nt.dump.idg/index.html > > I wonder whether this tells us more about WinNT, the Alpha platform's future, > or Compaq's financial state? > > -Ernst > _ > Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm > Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers > \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Free Big computer time.
So, I've run across a really nice computer that noone needs for a few months... Solaris 2.6; 4 Processors, 4GB Ram, 500GB of drive space... that sort of thing. Is there any useful project out there that can really make use of this sort of power? I mean, sure, I can run some factoring programs on the CPUs, but that doesn't really do justice to the RAM and the available Hard Drive space. And the system isn't available long term enough for me to commit to four separate large factoring projects (four exponents... whatever) really. Most of the stuff around doesn't parallelize very well either (well, not at the single computer level). Any ideas? Thanks, ---Chip \\ ^ // (o o) ---oOO--(_)--OOo-------- | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Meetings (was $100,000...)
> I like the idea of a symposium, I'll bet that colleges would be willing to > host it. In Illinios, we could host it at UIUC (Urbana), ISU (Normal), or > U of C (Chicago). Maybe we should set a number of these up. I would > personally like to meet the GIMPSers in the midwest. Just for completeness, I'm in Washington, DC... so I'm game for an East Coast gathering as well. ;-) Although I'd like to see one nationally... that's where prize money could come into play. As for research papers, judging from the conversations on the list here, I imagine some people could come up with topics. Either way, there's no reason that input needs to be limited to GIMPsters, especially if we host at a university. I think student papers are always interesting, and there are bound to be people out there who haven't learned of the glory of being in GIMPs. Maybe we could win some CPU years from the Bovine people, or the fledgling SETI people as a result. ;-) GIMPS is best! Or something like that. ---Chip \\ ^ // (o o) ---oOO--(_)--OOo---- | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Setu for Dual processor NT
> Use the -A switch (see the readme) to configure a separate image of the EXE. > ALso set the affinity (under advanced) when it is running so the processor > preference will be set in the control file (one image per processor). Is there any way to set the affinity under NT automatically when a service starts up? Some of the machines I run this stuff on are multi-os, and I very often switch between them, which means rebooting a lot. And I never remember to set my affinities by hand againwhen I come back into NT. It just kills performance in NT, tho, if you don't have the affinities set up right. Doe UNIX variants have the same problem? I.E. Naieve timesharing across CPUs with the huge resulting overhead? Just curious. ---Chip \\ ^ // (o o) ---oOO--(_)--OOo---- | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: The $100,000 award for 10,000,000 digit prime
The EFF of course, is offering the prize to help the advancement of just this sort of distributed computing (well, in a simplified nutshell). I don't think anyone should "profit" from GIMPS, but if we were to win a huge prize, I think we should use the money as it's intended. The idea of giving money for people who come up with speed improvements or large contributions to prime theory is a good one, and certainly anyone that incurrs expenses (Scott, George... anyone) should be reimbursed... this is a small part of these prizes. Here are a few other off the wall ideas... they should be taken semi-seriously; more as an exercise in lateral thinking than anything else. Beyond giving out the money in our own way, we could use it to increase GIMPs computing power in a few ways. If we started a non-profit organization, we could buy our own server farms with the money... Hell, we could double our speed right now by spending $50,000 on vanilla pentiums, a room, and a huge electric bill. I bet a few people on the group would volunteer time to keep it up. When the money runs out, donate the computers to a school or something; even then, the money then becomes well spent on continuing the computer industry, within parallel computing, and within education; a worthy cause. Or this... pay a computer manufacturer to subsidize computer sales to academia with the requisite that the Prime95 (or similar) software is installed ahead of time? Or just donate money to high-schools or colleges to buy computers with the requisite that they help the GIMPs project? Again, everyone wins, and noone feels greedy. OR... we could fund the production of sieving/LL testing hardware. I'd like to see a four inch square cube sitting on my desk running factor.exe all day. :-) Advertise... could you imagine advertisements for GIMPs in the Wall Street Journal? :-) Or a good spot on Cartoon Network or the Sci Fi Channel. Have a party... wouldn't YOU like to meet the other people working with GIMPS? Frankly, this wouldn't be THAT expensive, and we could even make it a symposium or something call for papers or research in the area of computational number theory. I could go on... but I imagine this is long enough, and people probably won't make it much further. Just some ideas. I admit, tho, that although I'm not completely sure what happend to the current prize money, everyone on the project should at least have a vote or a word in a discussion about what happens to it. Later, ---Chip \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: re: Mersenne prime exponent binary
> > Note that in the set of mersenne prime exponents (so far), the leading > > digit 1 (in decimal), turns up 10 times as opposed to the 4.2 times > > expected by equal leading digit distribution... > > Actually we should expect an excess of smaller leading digits over > that predicted by "Benford's Law" in this case. A smaller exponent is > more likely to be prime than a larger exponent, and a smaller prime > exponent is more likely to give rise a Mersenne prime than a larger > prime exponent. "Benford's Law" would follow if _every_ exponent > (prime or composite) was equally likely to give rise to a Mersenne > prime. But that's part of the interesting thing... the size of the exponent is only vaguely associated with the LEADING digit. I disagree that we'd expect smaller leading digits, at least noticeably many, since it's the order of magnitude, not just the leading digit that makes the nth mersenne prime larger or smaller. I mean M20 is some 50 digits longer than M19... at this distance, I don't see how the leading digit is affected by the larger likelyhood that smaller exponents would make more likely primes. But I'm probably wrong. This is what makes this a really interesting fact, tho, I guess. > > Yes. Though they were talking about the exponents... > > Weird, I would have thought that it wouldn't affect powers of > > two... > > Why not? Looks like a perfect model to me! In some vague attempt to not take the Benford issue off topic, it's interesting that numbers 2^n (for all Natural numbers n) follows the pattern VERY closely, but it's also interesting (perhaps moreso), that 2^p follows the pattern, as do (apparently) the Mersenne primes themselves, as do (from quick examination) the exponents for the mersenne primes. Thanks for adding this to the FAQ, btw. ---Chip \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm
Re: Mersenne: re: Mersenne prime exponent binary representationsand 1's frequency (incl M38)
I'm not sure what the law of leading digits is, but I read this as talking
only about base 10 numbers... so the leading digit 1 is compared to
leading digit 2, 3, 4, ..., 9. Right? So for numbers 2^n (in Base 10),
[or is it 2^p?] there are a lot more leading ones than one would "expect"
naievely (you would expect 1/9 to start with "1", I imagine).
Why this is, I have no idea... can someone explain?
---Chip
> > The law of leading digits predicts that, for decimal numbers,
> >log10(2) ~= 30.1% will have leading digit 1.
>
> Uh, won't they *ALL* have a leading digit of one? Anything with a leading
> digit of ZERO can be totally discounted
>
>
>
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Re: Mersenne: M38 in the news
This is a pretty good article... a few things I didn't know; someone should add a history section to the FAQ, for those of us that haven't been around too long. ;-) On the other hand, there are a few things that could be polished up in the article... to quote: "Although in theory an infinite number of primes could be found, this latest discovery is only the 38th to be verified." Close, anyway. ---Chip On Sun, 27 Jun 1999, Luke Welsh wrote: > http://www.oregonlive.com/news/99/06/st062601.html > > Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm > \\ ^ // (o o) ---oOO--(_)--OOo-------- | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm
Re: Mersenne: EFF and 10,000,000 digits (fwd)
Intel worked out a licensing agreement with Digital just before Compaq took over. It gave them access to almost all of the technology of the Alpha line, if I recall correctly. I don't think anyone actually bought the Alpha chips; the line stayed with Digital when it went to Compaq. IBM was not involved. If I remember, Intel had better research into smaller data paths (so and so many nanometers smaller than the Alpha line), but the Alphas had superior clock rates... the combination of those two technologies (and a million other miscellaneous marriages of technology) was suppossed to produce killer chips. Or something like that, ---Chip \\ ^ // (o o) ---oOO--(_)--OOo---- | Chip Lynch| Computer Geek| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | -- Forwarded message -- Date: Wed, 9 Jun 1999 11:13:19 -0700 From: Joth Tupper <[EMAIL PROTECTED]> To: GIMPS <[EMAIL PROTECTED]> Subject: Re: Mersenne: EFF and 10,000,000 digits Two things: 1) I do seem to recall a 1GHz Alpha announcement. 2) Was it Intel that bought the Alpha rights? It might have been IBM but was NOT Compac. Joth - Original Message - From: David L. Nicol <[EMAIL PROTECTED]> To: Aaron Blosser <[EMAIL PROTECTED]> Cc: Mersenne@Base. Com <[EMAIL PROTECTED]> Sent: Wednesday, June 09, 1999 9:28 AM Subject: Re: Mersenne: EFF and 10,000,000 digits > Aaron Blosser wrote: > > > > > I have heard some insider news that Intel *could* hit the 1 GigaHertz mark > > > by years end if they had a reason to > > Did DEC not demonstrate a gigahertz Alpha chip shortly before Compaq > purchased them? > > > David Nicol 816.235.1187 UMKC Network Operations [EMAIL PROTECTED] > "unpersuasive and dubious" > > Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm > Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm
