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or, make math history (and possibly win a couple of grand)

find the 40th Mersenne Prime

BTW, does anybody know where or in what file on your computer they store the SETI@home password? It MAY still be on my parents old computer.. somewhere amongst all the files... I WOULD like to recover it if possible.

I had sinced switched that computer to prime95 which runs all the time on the computer with little to no significant impact on the system; however, they barely use that computer anymore anyways, so now it's not participating in any project.

I currently run a few other projects on my own system. Basically, the SETI @ home project gets boring... there are other projects, as has been said that either 1) will impact scientific knowledge 2) have a definite end, or points of production when you feel like you actually are accomplishing something. SETI@Home proved it's point.. that millions of people are interested in the project, and also just willing to use their unused processor time to run a distributed computing project. Did SETI@Home ever get beyond their "this is an experiment and even though we have far outpaced our capacity, we won't open it up for other possibilities"? According to their own website, they are going to be winding down the SETI @ Home project and starting new ones over the next year.

IMHO, it uses up too much processor time, and slows down computers, whereas other projects I can run on even slow/old computers and not get it slowing down the system. Also, that 'pretty screensaver' gets boring, too, and technically it doesn't "save the screen" anymore because it repetitively displays the same images over and over again in the same place, not like most of us have to worry about monitor-burn-in anymore, BUT...

I'm still not exactly sure what I need all this speed for.

I'm running 2 Athlon dualies at home, and they've got MP processors in them. (Among other things, they search for Mersenne primes.)I kept up with the MP/XP debate on whether they were the same chip, and IIRC, the core is the same and the chips are essentially 99.44% the same. If you look up the whitepapers on the pin-outs of both chips, I believe there is a different signal on the MP chips' pins. It had something to do with something SMP-ish. (real technical, I know, but it's early) Yes, the XP's will run in SMP mode.

1. It's true
2. It is a viable product
3. reliable drivers become available
4. people buy them

In 2001, a 4 million decimal-digit number was proven to be prime. This is a single-bit result, but reaching it had taken 2 years of spare computing cycles on 205,000 computers (or something like that). That's a very expensive bit.

http://www.mersenne.org/13466917.htm

http://www.utm.edu/research/primes/notes/13466917/

AFAIK that is not the first project - GIMPS (The Great Internet Mersenne Prime Search) started before D.net.

If you want to know more or have questions about GIMPS, I would highly recommend you to visit (and maybe even join) Ars Technica Team Prime Rib, it's a very active team and they have great stats :)

The Great Internet Mersenne Prime Search. A Mersenne Prime is of the form 2^x-1. Five have been found so far through GIMPS.

If it's money you want, it's $100,000 to the GIMPS for the first person who can catch a ten million digit prime number, and then split up according to the rules on this page.

If it's nobility you want, the money is awarded by the EFF to spur on cooperative computing.

BTW, it was a Slashdot story that clued me in in the first place.

The Great Internet Mersenne Prime Search. A Mersenne Prime is of the form 2^x-1. Five have been found so far through GIMPS.

If it's money you want, it's $100,000 to the GIMPS for the first person who can catch a ten million digit prime number, and then split up according to the rules on this page.

If it's nobility you want, the money is awarded by the EFF to spur on cooperative computing.

BTW, it was a Slashdot story that clued me in in the first place.

Each project has it's own benefits. I completed 5000 SETI units and now I am looking for prime numbers. If you feel that strongly about medical research, then good for you. I did not like the bandwidth problems SETI kept running into. I decided my spare cpu cycles would be better spent elsewhere. I share the same concern others have expressed about how the medical research data will be used. Some companies think they can patent my genes :(

I recommend that people look at all of the distributed projects. I suggest that you can support more than one. We can learn from all of them.

BTW, the EFF supports GIMPS. Maybe I will get back that money I have been donating for the last few years ;-)

Every CPU can be pushed a bit more to the limit it has been given by god. You will get a faster system, without having to spend more money.
Money you could use to make the world a better place, or buy that girl next door some flowers. You can think of somthing yourself ... perhaps/hopefully.

If your oc'ed system didn't crash after 24hours of prime it won't do it while you're using your fav textprocessing tool, at least not because of the cpu. You just have to turn the speed back a notch, or some notches, if your oc'ed system is not stable.
WebTip: HardOCP.com.

If you have too much money ... you could just buy the highend CPU. Or buy one frequency step below the top end, save some hundred bucks, and feed a family in the 3rd world for some weeks.

Overclocking saves money. Saving money and spending it more wisely, will make the world a better place.

Sorry, always get carried away on that topic.

I'm not sure whether or not this is a good thing or a bad thing. Lemme elaborate.

Disclamer: I have never been part of SETI@home; I feel that statistically it's a collossal waste of time. I've been part of both the GIMPS project and the distributed.net RC5-64 projects for about four years now. I've got the Kevlar body armor halfway on.

The good, I guess, is that there's such a collossal interest in this. I mean, hell, if KzAplOcQQ and boB are sharing the Encyclopaedia Galactica (or the Hitchikers' Guide, whatever) over radio waves, then we'll eventually find it hopefully in something that resembles paEr Unicode.

However, I see a great many downsides to this.

First off, if the aforementioned theoretical KzAplocQQ and boB of the paEr race have to use radio waves, then there's a pretty good chance they haven't been able to go superphotonic, in which case we're going to have a long wait before we can even think of going to their New York and flipping them the left tentacle.

Secondly, how will we be able to decode a xenic dataset, much less their language? I mean, what if they can transmit trits or quaytes while we're looking for bits or bytes? How do we know what a newline would appear? Hell, do we even know if it would even be necessary? And what about the characters? What if the Chinese language is easier to interpret than paEr?

Third, there are much better uses of free cycles, at least fiscally. GIMPS will provide a hundred kilobucks to the first person to successfully find a ten megadigit Mersenne prime. distributed.net provides a two kilobuck prize and a large donation to the FSF, EFF, or other worthy charities. Even the commercial distributed computing projects at least pay for the use of your rig.

(PS: paEr is a theoretical name for a xenic (alien) species, contrived from randomly entering characters on the number pad. KzAplocQQ is an unpronouncable name, unless you're lucky or high. boB just sounds funny.)

Well, if you're factoring large primes it is

Can someone submit a patch, please? We don't want ET to think we're complete retards.

Does anybody know what the number actually is? And isn't it a bit odd that it hasn't shown up as news on either the GIMPS Home Page or the PrimeNet Home Page yet?

Does anybody know what the number actually is? And isn't it a bit odd that it hasn't shown up as news on either the GIMPS Home Page or the PrimeNet Home Page yet?

The Great Internet Mersenne Prime Search keeps all the large milestones here:

http://mersenne.org/status.htm

They haven't added #39 yet, but they probably will by the end of the day!!!

It's pretty easy. Believe it or not, the method to check whether they are primes or not involves FFT's. This means that integers are turned to floats to make use of the newest instructions available to processors today. Then, they are turned back to ints at the end of each iteration. Some checking is done to verify that nothing was lost in the rounding.

If something is lost in the rounding, the next person who does the check will find it. When they start the first iteration, a random seed is picked. At the end, the seed is "subtracted" from the residue. The residue will exactly match the residue from the first person who ran the primality test.

The float-to-int rounding error would cause the two testers to have entirely different residues. Also, there is no way to create the residue except to run the full primality test.

Of course, I should be referring you to the official FAQ's. But they're crappy.

If you want a good faq about the math of the system, read the mailing list FAQ's. These are much more interesting.

Ok, now, out of all those computers, a few of them are Macs, a few of them are Linux boxes, and a few of them are Win9x boxes. ALL the rest of them run WinNT4 or Win2K. And on all of them (except the Macs), there is some verson of prime95 running. That's a whole lotta P-90 years.

Please, join in the fun. Go to www.mersenne.org to join. You've got an approximately 1 in 100,000 chance of winning the next EFF prize for finding a 10,000,000 digit prime number. That's way better than playing the lottery folks!

Two years ago this project discovered the largest known prime number ((2^6972593)-1).

A prize of $100,000 has been offered for discovery of a 10,000,000 digit prime number. Unfortunatly the calculations required to test one such number will take about a year.

Find out more here.

I prefer projects with a higher probability to make an actual differene to how people live, like the (already named) Folding@Home, Genome@Home, or FightAIDSatHome. The last one may not appeal to many here as Entropia, the distributed computing network behind it, apparantly insists in throwing in some commercial work packets to the clients. Finding a cure for AIDS sounds like a splendid idea, otoh.
My personal favorite is GIMPS, the Great Internet Mersenne Prime Search, discoverers of the four largest explicitly known prime numbers. I like them because you actually have a chance to understand what the program is doing (if number theory is for you, that is). IMHO better than looking at some blinking lights of a screen saver that looks for ET.

Alex

There's even a $100,000 prize for the first 10,000,000 digit prime number. I encourage others to consider this project -- RC5 is close to pointless now (RC5/56 proved limited encryption is of no value), and SETI@Home already have more cycles than they can use.

Get real. SSE, 3dnow and MMX are hacks. Until any of these happens to entirely replace the functions of x87 FPU, the true compiler advantages of SSE is useless..

That is, of course, you equate how fast Quake runs on a P4 to how many Queries you have on your server running at one time, or how much longer until you find out if the Mersenne number you're testing is prime.

This situation seems to be about the same, he basically did no harm (the GIMPS client is very well behaved, and I can't think that the Dnet would be much worse), but it basically boiled down to the fact that he didn't have permission. What seems to be different is that this guy is facing huge criminal charges, I don't recall that Aaron faced any jail time or fines, but was still slapped around by the FBI (mostly out of cluelessness) for a long time.

But there are better things you can do with your CPU cycles. There are several actually useful distributed computing projects out there, like the protein folding project others here have mentioned. Or maybe you would prefer to help dseign new genes. Or surely you could find something you might like.

Personally, I think SETI is pointless

It may be unlikely, but least it is theoretically possible for SETI@Home to produce significant results. However, the RC5-64 is guarenteed not to produce any useful (or even interesting) results. It will teach us nothing we don't know already.

it doesn't hurt me at all that if my machine happens to find the key that I get $2000

If you want a shot at winning a prize, you could try looking for huge prime numbers. While that doesn't seem to be particulary useful, at least the money is better. And more importantly, you won't spend years searching for something we already know.

You think SETI is pointless but cranking on a problem that is known to have a solution is not? If you want something significant that doesn't have a known outcome, try OGR from d.net or look for large prime numbers - at least these projects will create some new knowledge (and OGR actually has some practical applications as well), whereas we already know that given enough time, the RC5-64 key will eventually be found.

... could we please get back to work and use all
that power on something meaningfull, such as finding mersenne primes or Optimal Golomb Rulers.

RSA wanted to prove that neither 56 bit and 64 bit encryption isn't enough and that it is possible for a small crack senstive information protected by 56 or 64 bit encryption.

It will take som time to finish the 64-bit RC5 challenge, but it can be done.

Question is should it be finished? Not in my oppinion! Sure they will win $10.000, but that's about the only positive I can see in this. Used wast amount of power and computing time in doing so, only to give RSA reason to sell 128-bit RC5 and argue that it really is secure.

Wote with your CPU power and switch to something we all can benefit from. Larger primes and OGRs are candidates, but I'm sure there are others.

I recognized it only because Mersenne primes were covered in a book I read as a kid (Excursions in Number Theory). This formula was considered interesting for a couple of other reasons (which I forget) from Euler.

A society with a history in number theory may have run across this same thing; I've never seen it anywhere else. Naturally there's a web page for it.

But this prime number transmission is actually cool and should motivate people further in searching for new largest known prime . Imagine one of the first things another civilization reads is your prime!

Something for your great great... ...great great grand children to brag about.

Another option, in the "pure math" category, is the Great Internet Mersenne Prime Search at www.mersenne.org.

Using a computer to play DVDs is something of a hack anyways. You have to have a GOOD TV out, buy a remote for it, tweak the computer, maintain it, make sure all the fans are quiet. The hardest part is finding quality stuff because PC stuff in general is junk IMO, you have to make sure you are willing to spend extra money for better components if they are available. I'd recommend the Creative DXR3 with Hollywood + drivers, that card is pretty good, but no component outs, although there might be a hack out for that.

Instead of worrying about getting decent analog output from your computer, you could just park a monitor in your living room. 19" monitors aren't much more expensive now than good 19-20" TVs, and it's my understanding that HDTV-capable tuner cards are supposed to be fairly cheap as well. It could be a way to get into HDTV without spending thousands, if you have a computer you can dedicate to doing video work (when it's not doing anything else, you can have it find Mersenne primes or something).

"But a 19" monitor is too small for TV," you say? I hate you. :-) (I don't have the space for something much bigger than the 20" Panasonic I have now, and even if I did, I don't know if it'd be worth springing for a bigger TV anyway.)

For a while, I had a K6-200 with a Riva 128 (came with TV-out) and a Creative Labs Dxr2 kit running Win95 and rigged as a DVD/MP3 player. Playing that stuff now has mostly been relegated to an Apex AD600A (one of the "loophole" models), though the computer is still under the TV, running command-line Linux to provide another place to read mail/news and play MP3s across the network. Maybe it'll get an HDTV card someday, if such a card doesn't need a GHz Athlon/P!!! to drive it.

A single CPU server is like... well... crap.

It depends on what you're serving. I have most of one company's email going through a cast-off P5-166. It has only about a gig of storage (and that's split between two smaller HDs), but that was enough for SuSE 6.3 with the usual stuff needed to serve up email to about 40-50 addresses via POP3. The only time we've had a problem was when dyndns.org went down a couple of months ago, and that was beyond our control. The machine's been up nearly eight months now without a reboot and shows no sign of trouble. (When it's not shuffling mail, it's crunching primes...the load average is always >=1.00.)

A dual-Xeon would've been overkill.

I donate all of my spare cycles to the Great Internet Mersenne Prime Search (not the Great Internet Prime Search). There is software available for many platforms (including Linux) here. This project currently holds the world record as the discoverer of the largest known prime.

I donate all of my spare cycles to the Great Internet Mersenne Prime Search (not the Great Internet Prime Search). There is software available for many platforms (including Linux) here. This project currently holds the world record as the discoverer of the largest known prime.

My favorite distributed project is at http://www.mersenne.org where you can help find a mersenne prime number. If you are the first one to find a 10 million digit one you can win $55,000. It has support for Windows 95-2000 (& NT), Linux, FreeBSB, OS/2, DOS, and Windows 3.1. You can download it here.

My favorite distributed project is at http://www.mersenne.org where you can help find a mersenne prime number. If you are the first one to find a 10 million digit one you can win $55,000. It has support for Windows 95-2000 (& NT), Linux, FreeBSB, OS/2, DOS, and Windows 3.1. You can download it here.

Or, since there might be, oh, say, one or two math geeks out there...

Check out PiHex at http://www.cecm.sfu.ca/projects/pi hex/pihex.html

Calculate pi further and further and further and further...

And yes, they even have a "top producers" thing for you crunchers.

There's also http://www.mersenne.org/ with a list of distributed projects...

May I suggested the new Optimal Golomb Ruler project over at Distributed.net. Searching this space can only be done exhastively, and is actually useful (in, admittedly, rarified areas). The Great Internet Mersenne Prime Search is another project where the work will actually have lasting use.

Not to take away from Seti@home -- interesting project. It just became TOO popular. Ditto RC5 -- the project probably helped force the restrictions to be lifted, but it's point has been made; why spend another two years or so on it?

GIMPS, the Great Internet Mersenne Prime Search still needs your CPU cycles. It's good math, and can use all the CPU it can get, and it's found four of them already. It runs quietly in the background, and cooperates will with firewalls and with full-time or part-time internet connections. I don't recommend running it on laptops using batteries, since it eats power, but it's fine for any machine that's plugged in.

I think the best distributed processing project I've been involved with is GIMPS, the Great Internet Mersenne Prime Search.

Mersenne numbers are numbers of the form 2^p-1, (2 to the pth power minus 1) Generally, when Mersenne numbers are mentioned, Mersenne numbers with prime exponents are what is actually meant. The Mersenne number 2^p-1 is abbreviated Mp.

A Mersenne prime is a Mersenne number Mp which is prime. P must itself be prime, otherwise Mp has a trivial factorization. Namely if p is divisible by a and b, then 2^p-1 is divisible by 2^a-1 and 2^b-1. More generally, gcd(c^a-1,c^b-1)=c^(gcd(a,b))-1.

So basically, what it boils down to is that you can test the primality of a Mersenne number a lot faster (Using a Lucas-Lehmer test), with a computer and find REALLY big prime numbers. For example, the biggest prime # found to date is the Mersenne Prime where p=6972593 which has 2,098,960 digits in it.

The EFF is offering a $100k award to the first person to get a 10M digit prime number.

I highly suggest you switch from boring old D.Net or SETI@Home and go for finding big prime numbers

Actually, there is a proof that there is no largest prime number. To use it, you need to know the Unique Factorization Theorem (which I'm not ready to explain on /.)

I just realized that you had a "known" in there... Yeah. The largest known prime number is of the form (2^p)-1, also known as a Mersenne prime.

IIRC, there was some slight change in icons or something in the W98 UI that was kind of the same thing, just different enough to make it distinguishable from 95.

They made the menus "slide" open instead of having them just pop up. This "feature" is one of the first things I turn off when I install/reinstall Win98 on a computer, and if I'm using someone else's computer for any length of time, I'll turn it off on that computer. Less CPU time for GUI frills means more CPU time for Prime95. :-)

The link's broken. Do you by any chance mean GIMPS?

www.mersenne.org List of distributed projects that make sense (at least some of them) in contrast to most distributed.net projects. Once the distributed RC5 cracking make sense, but now it is pretty useless as the computing time is just an extrapolation of the time needed to crack the other messages...

1. SETI@home
2. GIMPS: The Great Internet Mersenne Prime Search

Another worthy distributed math project is GIMPS (Great Internet Mersenne Prime Search).

More on Mersenne primes here.

PiHex

Mersenne Primes

Seti@home

Why do this? Well, first my ultimate goal is not stats-oriented. I don't really care where I am in the stats, where my team is in the stats, etc. What I enjoy most is that I contribute to a number of projects, albiet a little in each.

For example. The Seti@home client runs on a Pentium 166 (overclocked to 200) that is sitting in the living room of my apt. It makes my roomates happy to see eye-candy on the monitor out there and it keeps the otherwise idle machine (it's a proxy/firewall for our cable modem connection) doing something. No, it doesn't zip through data blocks (about 1 every 5 days or so), but it is doing _something_.

So, what's my point? (I'm asking myself that same question). Basicly, it's that people participate in distributed computing projects for various reasons. If Seti@home has brought 1.6 million people into the distributed computing fold, then more power to them! (I do contest their figure of 1.6 million people participating, but that's for another discussion). Even if the client is not 100% efficient (and what software package is 100% efficient?) they are still contributing to the overall education of people in matters of distributed computing, in particular internet based projects.

Finally, it should be noted that distributed.net re-did a large number of CSC data blocks (~25%) as a security measure to reduce/eliminate false-positives from making their way into the stats.

Believe it or not, there are some people who don't believe in extra terrestrial intelligence. And those people aren't all psycho fundies either. We choose to work on Distributed.net because to us, it's far more purposeful than seti at home, which would be like looking in an empty box for...something.

We could also run Prime95 but I would rather discover how easy (or hard) it is to crack encryption than waste my cpu cycles looking for a bigger prime number.

So, given the choice between looking for something in an empty box, or finding the next big prime number (which does, um, nothing for number theory) we choose to crack codes, which might prove useful (primarily in discovering what kind of computing power is necessary to do it).

Jeremy

yep, and their "announcement" killed the existing OGR project. Kind of like Microsoft pre-emptively announcing products to kill their competition.

mersenne.org has lots of links to more scientifically interesting distributed projects.
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