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(Mostly) Confirmed: New Mersenne Prime Found 331

A reader writes "Distributed computing seems once more to be succesful. The combined effort of many pc's joining Primenet in search for a new Mersenne prime may have found there fifth result. Among them many belonging to /. readers. There is an unconfirmed claim for Mersenne prime #39 of over 3,500,000 digits, for which a considerable amount of money has been awarded. SETI looks for ET's messages, but found none sofar. Mersenne primes are used to tell ET about us. A previous found Mersenne number was used to show the advance of science on our planet in a message send into outer space. " The Primenet list has confirmed that while they still need to totally test it out (which should be done by the 24th), they believe that the number found today is the 39th positive.
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(Mostly) Confirmed: New Mersenne Prime Found

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  • just think (Score:3, Insightful)

    by Anonymous Coward on Wednesday November 14, 2001 @04:20PM (#2565727)
    just think if we dedicated all this computering power to a relevant problem...and before you ask, i'm a grad student in math, so don't call me out of touch with mathematics. i just think there are plenty of better problems (including w/in mathematics) than this, of course, why does my opinion matter?
    • Re:just think (Score:5, Informative)

      by erlando ( 88533 ) on Wednesday November 14, 2001 @05:09PM (#2566098) Homepage
      Some of us do use our otherwise wasted idle-cycles for something useful:

      Cancer drug research [ud.com]
      Gene research [stanford.edu]
      Protein folding [stanford.edu]

      All of these distributed projects reach into medical research and are as such a bit more useful than searching for ET [berkeley.edu] or cracking RC-5 [distributed.net].

      • Yeah.
        I've got to say that I'm disappointed in how popular distributed.net RC-5 cracking is. What the hell is the point? The only reason we don't have the key is because they destroyed the hard drive from the computer that generated it. It's easy to calculate how long it would take to find a solution by brute force (which is what they're doing) without actually wasting all of those cycles.

        SETI@home seems rather like pseudoscience to me (And without source, I wouldn't be surprised if it's a secret plot from the NSA ;)), though I suppose this is a kind of fun one. At least we don't already know the answer.

        I like GIMPS (we are at least learning something new and the results are easily verifiable), though the bio ones you mention are also very neat. Let's hope that more useful projects come out of this idea...
    • Well, you use primes in encryption for instance in PKI. Dsa signatures use them too. So it is useful, though not as helpful as say, the cure for cancer.
  • I believe distributed computing has a lot of potential. Even though we are still in the early stages of it look at what has come out of it. It just amazes me that I can help find new prime numbers or search for ET from the comfort of my home. ( And without frying my brain thinking about it )
  • until the 10 million digit mersenne prime is found, if one exists.

    very interesting... but hey, this should pump a few more clients into SETI@home, rc5, and the rest of the bunch.
  • by iforgotmyfirstlogon ( 468382 ) on Wednesday November 14, 2001 @04:24PM (#2565751) Homepage
    ...hasn't found this number is prime yet? Won't he/she just think this 3,500,000 digit number is a bunch of gibberish?

    - Freed
    • yeah, probably. ET was too busy building spaceships and death rays.
      on the eve of armageddon, we'll all be hearing "bwa ha ha ha! foolish humans! what have your prime numbers brought you? nothing! you have wasted your precious resources, and now you will pay the ultimate price! except for you, Linus, you've got some good ideas..."
    • So what if ET hasn't found this number is prime yet? Won't he/she just think this 3,500,000 digit number is a bunch of gibberish?

      The assumption is that if ET is out there, he's a lot more technically advanced than we are. Human civilization has been around for, oh, call it 8,000 years. The universe is more than a million times that age. So ET has a big head start.

      My theory is that the universe is teeming with life, but everyone else is smart enough to keep a low profile. Only the humans like to broadcast to the universe an exact measure of how technically backwards we are.

      • And what would be the point of keeping a low profile? So the other civilizations that are 200,000 light years away don't send you a mean message and make you cry?
      • my theory (Score:5, Interesting)

        by Anonymous Coward on Wednesday November 14, 2001 @05:04PM (#2566059)
        My theory is that they're gone. I mean, really think about it:

        20,000 years ago we were going around grunting at each other and living nomadic lives

        10,000 years ago we finally began to make small villages, and practice agriculture

        500 years ago we finally got the technology to send ships from Europe to North America

        200 years ago people still read by candle light, died of infections from wounds, had no telephones or radio

        100 years ago people still got around by horse and buggy

        60 years ago people did the most complex math problems by hand

        30 years ago NASA sent people to the moon with the computing power probably about what is found in a TI-89 calculator

        20 years ago no one had ever heard of the internet, and computers were slow and text-based

        10 years ago computers started to be a household necessity

        5 years ago the internet took off

        1 year ago the human genome was mapped

        The point is: find someone from 50,000 BC ago and take them forward in time to 15,000BC. they probably wouldn't see a damn bit of difference

        you could keep doing that for people of different ages, and the amount of time you could bring them forward without them really not being able to adjust to the massive changes in society would just get smaller and smaller. the time is getting so short now that a person can span it in a lifetime. we have middle-aged people today who are afraid to use computers.

        Now try to imagine 100 years into the future. Pretty tough. Might we have real AI? Humans on the Moon and Mars? Computing implanations? Nanotech? Quantum computers? Yep. Pretty shocking. But now try to imagine 10,000 years into the future. It's impossible. IMO there is a very good chance that there will be no such thing as humans, as we know them, 10,000 years from now. We will have advanced into something better than these meat and bone bodies.

        And the 20,000 years(max) from when humans first set down roots, and when they will no longer exist as humans, is nothing in galactic terms. It isn't even an eye-blink.

        I think any civilization more than about 500 years more advanced than us might actually be *undetectable*. Maybe they exist as pure energy. Maybe they have transcended this universe altogether. Maybe they are studying us right now, but we don't know it because they are doing it from the 4th dimension(like a 3D being looking down on flatland).

        I simply think anything beyond the near-future is impossible to even speculate on. The singularity. The end of history. Whatever you want to call it. It will be the end of the human race as we know it.

        • The search for intelligent life? Ok lets say aliens saw our radio signals, either they'd laugh at us as we laugh at monkeys in the zoo, or they'd enslave us.

          Really we dont want either of these situations ot happen, but really you make a good point, with nano technology and say brain to computer interface and AI, we wont be anything like what we are now, we will most likely be meta physical, most likely be able to transofrm matter into anything we want, most likely have telepathy via advanced communications technologies. If this is us in a few hundred years, then if we are looking for aliens that are millions of billions of years old, chances are they already know where we are and what we are doing and are laughing at us right now.

          Think about it, anything thousands or millions of years more advanced than us would be like gods to us, literally.

          Hopefully we dont end up attracting evil aliens who want to turn us into their pets ,slaves, or put us in zoos like we do monkeys and wild animals. But hey, thats the chance you take when you waste time with Seti and give aliens a complete map to the solar system (as if they dont already have one) and give aliens our DNA (thats the dumbest possible idea every thought of)

          Giving aliens our DNA means, any group of aliens can simply use our DNA to look exactly like us and blend into our population and we would have no way of knowing it

          of course idiots at seti and other fools who send stupid probes into space without thinking first, believe aliens will be as dumb as us and havent mastered what we dont understand.
    • Generally such messages are designed to illustrate mathematical concepts. As such, I highly doubt they only sent one particular prime. Really, there isn't much of anything that we can send that's guaranteed to be intelligeble to an alien culture. They may not even share our fascination with prime numbers - while eminently useful to us, they aren't nessecary for things like engineering.
    • [So what if ET] hasn't found this number is prime yet? Won't he/she just think this 3,500,000 digit number is a bunch of gibberish?

      They'll probably figure it's our Galactic ICQ number.

      Seriously speaking, if they think at all like us, they will figure that the number has some special property and start testing it. Testing a number for primeness goes much faster than searching for new primes. Having discovered that it is indeed prime, they will know just how clever we are and hopefully be so impressed that they will decide not to devour us.

      • or, being consumed by their thought that they are and should be the only intelegent beings in the univers, will come down and destroy our planet out of fear that one day we will surpass them in thechnological abilities and become the dominant beings in the universe.
    • Especially since it will probably be transmitted in binary, and look like:
  • Perspective. . . (Score:1, Insightful)

    by czardonic ( 526710 )
    That we devote this much co-operation, time and energy to the quest for prime numbers while hatred, poverty, disease and environmental destruction continue to plague our race is hardly an advertisement for our planet's advancement.
    • by cburley ( 105664 ) on Wednesday November 14, 2001 @04:35PM (#2565830) Homepage Journal
      That we devote this much co-operation, time and energy to the quest for prime numbers while hatred, poverty, disease and environmental destruction continue to plague our race is hardly an advertisement for our planet's advancement.

      Yes, and we're all awaiting your proposal for how to use a bunch of idle PCs and bandwidth to wipe out hatred, poverty, disease, and environmental destruction.

      Until you get back to us with that, stop complaining about how we entertain ourselves, okay?

      • stop complaining about how we entertain ourselves, okay?

        There is a difference between entertaining yourself and demonstrating the advance of science on our planet. Some endeavors might acheive both. As far as I can tell, this does neither.
      • Here's my proposal....we can all use our idle CPU cycles to send out massive amounts of spam preaching love and tolerance, and for the hungry people techniques for good agriculture.

        All the worlds problems solved, just like that!

    • by Microlith ( 54737 ) on Wednesday November 14, 2001 @04:37PM (#2565850)
      That in spite of all the bad things happening, people can give all those who would tear them down the middle finger, and continue on in purely academic research?

      I think PART of humanity has advanced, but those who:

      a) cause misery
      b) profit off misery
      c) whine about misery

      haven't really gotten anywhere.
      • by czardonic ( 526710 )
        I think PART of humanity has advanced, but those who:

        a) cause misery
        b) profit off misery
        c) whine about misery

        haven't really gotten anywhere.

        You forgot:

        d) crow about how smart they are and squander their energy on trivialities.
  • 3,500,000 digits is only 1/3 the length required for the major ($100,000) payoff. We still have a long way to go for that one....
  • by Audent ( 35893 ) <[audent] [at] [ilovebiscuits.com]> on Wednesday November 14, 2001 @04:27PM (#2565774) Homepage
    First: distributed computing achieving something great. Don't get me wrong, I'm all for SETI, I've got it running on both my machines ... but being able to advance science be it math or cancer research or whatever is astonishingly cool.

    Second: it's entertaining to think we can prove our intelligence to another species by sending them proof that we've cracked a prime ... If they're astonishingly more advanced than us they'll look at it as being quaint and if they're not they'll look at it as something they can't understand. How would we react if something landed that proclaimed how smart the sender was?
    Of course, if they're "looking" at the wrong frequency or in the wrong band they won't see it at all... so many assumptions... so little time.
    • F SETI@Home (Score:1, Redundant)

      by joshamania ( 32599 )
      You can help cure cancer with http://foldingathome.standford.edu [stanford.edu].
    • Considering the small timeframe humans have been civilized (10k years?), the chance that we are at anything but a severely inferior technology level is remote. Any advanced races would probably be comfortable in dimensions we can't even imagine, and probably be aware of humanity without us trying to contact them. We know an ant hill is there without being able to smell the phermones they use to communicate, right?

    • Second: it's entertaining to think we can prove our intelligence to another species by sending them proof that we've cracked a prime...
      Yup. Very entertaining.

      Until the alien lawyers arrive, waving around the Encyclopaedia Galactica version of the DMCA, and sending us all into oblivion with their phasers, torpedoes and subpoenas, for cracking part of the encryption to Life, the Universe and Everything.
  • Prime stamp (Score:2, Informative)

    http://www.utm.edu/research/primes/mersenne.shtml [utm.edu]
    After the 23rd Mersenne prime was found at the University of Illinois, the mathematics department was so proud that they had their postage meter changed to stamp "2^11213-1 is prime" on each envelope.

    Does anyone have an envelope with this stamp on it?

    • i feel obligated to correct you:

      3**2+ 4**2 == 5**2 ...

      so -- Andrew Wiles a**n + b**n != c**n for n>2.

      anyway, wiles et al actually proved the taniyama-shimura conjecture that all elliptic curves are modular. someone had already noted that fermat's last theorem and the taniyama-shimura conjecture were equivalent.

      </anal retentive rant>
  • What if... (Score:5, Funny)

    by ellem ( 147712 ) <ellem52@@@gmail...com> on Wednesday November 14, 2001 @04:32PM (#2565804) Homepage Journal
    ET has no concept of our numbers?

    I always find the idea that ET is "like" us somehow. That Will Smith can get into and operate an alien spaceship.

    Zog: Mumtar! The Earthlings have sent us I Love Lucy and now what appears to be a very large cable bill!

    Mumtar: Destroy them!

    • If ET doesn't understand mathematics, its unlikely ET progressed as far as building radios, either. Prime numbers are a fairly simple mathematical concept, one thats been found by every human society developing a complex system of mathematics. It's not simply some artifact of the decimal system. Prime numbers are prime in any base. Once you've got whole numbers and division you're pretty quickly going to come to the conclusion that some of them can't be divided by any of the others.
    • What do you mean ET has no concept of numbers? How will we upload Macintosh viruses to their computers if he doesn't even understand numbers?
    • If they don't understand numbers than they will not be able to receive the communication anyway. They're not *our* numbers. Numbers are discovered, not invented.
  • by joshamania ( 32599 ) <jggramlich&yahoo,com> on Wednesday November 14, 2001 @04:32PM (#2565807) Homepage
    I really wish that more folks would look over at Stanford's Folding@Home Project [stanford.edu] . I personally think it is the single most important and fascinating distributed computing project available. Just think, instead of searching for obscure numbers, or aliens, or trying to break the latest RSA key, you could be curing cancer with your spare CPU cycles!!!
    • Does this folding@home thing actually work now? I downloaded clients to several machines and was disappointed at how broken it was. My cycles have continued to go for distributed.net and seti@home ever sense.

      Granted, it was awhile ago when I tried the folding@home stuff, but even the uninstall was horribly broken and it looked like something that really shouldn't be on any computer that couldn't be trashed.

      • They recently released a 2.0 version. While there still is no screensaver for Linux, I've been running the console version for weeks now with much success.

        The windows client is muchmuchmuch better now too. It doesn't only act as a screensaver, but a background console that runs on spare cycles.
    • Genome@home [stanford.edu] It does similar things, and is also by PandeGroup. My team gave up on Folding after we had too much trouble with the client, and genome seems much better (of course, Folding has also most likely improved)
    • Why are there more of these projects? I myself, am participating in this [intel.com] one, or rather this [ud.com].

      I used to run moo! (distributed.net) - then SETI@Home, then back to distributed.net. But now I am glad I found this one, makes me feel good to know that I could help cure cancer! I know a few people that could have used one :(
    • I think that if these things were actually going to cure cancer, the ACA or other groups would donate the money for real supercomputer time to the project.

      People are dying NOW from these terrible afflictions. It's not a little open source hobby or a grad project, it's serious medicine. If the creators are willing to treat it as a toy then I'm not going to donate my CPU cycles to them - they're better off being wasted on Kazaa for my porn downloading pleasure.
  • Participate! (Score:4, Insightful)

    by chuckw ( 15728 ) on Wednesday November 14, 2001 @04:34PM (#2565819) Homepage Journal
    Please, join in the fun. Go to www.mersenne.org [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!

  • What do you get if you save the prime as something.zip and unzip it?

    Something juicy?
    • First it was a .gz file that was the prime number that gunzip'd into DeCSS. That is relavant because .gz files can have an arbitry amount of junk tacked on the end and still be valid. So the person just gzip'd decss.c and then added enough junk to make it into a prime number.

      Second a Mersenne prime is all bits 1, so you'll never have a valid gzip header to start with.

      So no luck there. But if you were to gzip the number it would compress up real well.
  • Mersenne primes are used to tell ET about us.

    I wonder if it'll encourage or dicourage them from making first contact with us if they think we're all a bunch of math geeks with too much time on our hands?
  • a friend of mine in dallas has a marsenne prime as a phone number and, even cooler, and a number away, also the result of a prime factor as yet another number... please don't crank call him!
    • Relavent limerick for the day:

      There once was an engineer named Paul,
      Who had a hexagonal-shaped ball.
      The square of its weight
      with his pecker, plus eight,
      Is his phone number, give him a call!

      - Freed
  • A previous found Mersenne number was used to show the advance of science on our planet in a message send into outer space.

    Yup, ET is going to get our message and probably laugh, "Ha ha, what morons, they've only found the 39th one! Lets defeat their pitiful technology, take their resources, and make them slaves! Muhahahahah!"

    How's the quote go? It's better to keep your mouth shut and leave people wondering if you're a fool, than to open it and prove that you are.

  • ... just as soon as i get my hands on a $415 thous [slashdot.org]
  • Geez... it's just a bunch of "1"'s. No information there...

  • After the 23rd Mersenne prime was found at the University of Illinois, the mathematics department was so proud that they had their postage meter changed to stamp "2 ^11213-1 is prime" on each envelope. Meanwhile, the humble physicists continued tests on thier time-travel prototype by sending an beaker into the future, wrote it in thier logs, and went home and ate bologna sandwiches.
  • by IdocsMiko ( 534405 ) <idocsmiko@@@idocs...com> on Wednesday November 14, 2001 @04:44PM (#2565902) Homepage
    Please don't volunteer for PrimeNet unless you are willing to devote yourself to the project. Too many people are signing up only to realize they are too busy for the task at hand.

    If you can't do the time, don't do the prime.

    (snort, snicker, guffaw, I can die a happy man now)

  • What most people don't tell you about the SETI@home project is that there are far more people processing the data than there is data to process. Most of the packets you're downloading to scan have been scanned dozens of times already--there just isn't enough data to justify all that computing power.

    Now, if we built more radio telescopes [setileague.org]...
  • Why do we assume that math is the best way to impress extra terrestrials? If it impressed _us_ it would be incorporated into a reality show or a saturday morning teen sitcom.

    I think the ultimate endeavor of human achievement is Truckzilla. A truck that can eat other trucks and breathes fire. I can see the aliens talking to each other ... "Sir, the terrans are too primitive for us to contact ... all we can receive are long numbers and primitive drawings ... Wait! It seems they have finally developed a truck that breathes fire and can eat other trucks! It's the only true measure of a sophisticated civilization."

  • Seriously -- not speaking from a naysayer standpoint or as somebody who thinks that SETI is a complete waste of time, although I am both of these -- what if ETs don't do math?

    I know, it's hard to fathom. But imagine this: human appreciation of art and life is rarely build on logical thought. When I say that my favorite painter is John Kacere, it has nothing to do with the trigonometry of his brush strokes and everything to do with what I like, a much more concept ideal. Conversation is a way of attempting to apply logic to what is essentially an illogical process, to explain a biological reaction with words and phrases.

    So what would I think if Chewbacca beamed a thirty meg prime number into my PowerBook? I sure as hell wouldn't pick up instantly on its nature. I'd probably try and run it through a gif converter or play it on Audion before I'd think to perform the three year process that would uncover it as a prime number. If we're trying to make contact with primes, it seems that we're restricting our target intelligence to creatures smarter than me. Which seems defeatist. Why not start smaller, with a fibinacci sequence or the differential calculus or a DivX file of "The Facts of Life" (divx having been developed in less than a year)? Don't we realize that they'll want to check our math even if they do figure out what the stream of gibberish we're sending is all about?

    And finally, what are they going to think when it gets there? Ifome superintelligent race of beings gets a message of a fact they already knew from a race of eggheads in the unfashionable end of the western spiral arm of the milky way, they're not inviting us to the intergalactic luau -- they're taking that hot race of Beings of Pure Sex from Omicron Six!
    • Well, I think it would be pretty hard for someone to devise a scenario where :

      a. some beings have reached the point (technologically, biologically, or otherwise) where they can recieve our message.

      b. they "notice" our message as not standard electromagnetic emissions

      c. they do not know anything about math

      I think A or B implies not C.
      • You claim that any being advanced enough to notice our signals would be sufficiently advanced to understand at least some math.

        Not necessarily. For example, I can observe frequencies in the range between roughly 2x10^1 Hz to 2-4x10^5 Hz (sound), and 4x10^14 Hz - 7.5x10^14 Hz (visible light).

        Please correct me if I'm wrong, but I think SETI is scanning in the 1x10^9 Hz to 1x10^10 Hz range (microwave). This leads me to assume that we are hoping that any alien beings are sending (and presumably listening for) signals in this range.

        Would it be a stretch to imagine those alien beings having the ability to directly sense microwaves, similar to our ability to see and hear?

        Since even a human child can see without knowing even basic math, perhaps our alien observers would be in the same situation.

        Just a thought.
        • Would it be a stretch to imagine those alien beings having the ability to directly sense microwaves, similar to our ability to see and hear?

          No, that's entirely reasonable, but at any realistic range the signal is so weak that you'd need a bloody great big dish to concentrate that signal enough to "hear" it. I find it somewhat implausible that there are creatures that have evolved into radio telescopes :)

          If they can construct a radio dish (even if they just use it like a reflecting telescope to shine the radio waves into their microwave "eyes" they'd presumably have to know at least a little geometry.

  • When I go to http://www.mersenne.org/, I get a large yellow screen saying "Distributed Com", and a few borders, and nothing else. Are they using DCOM for this?
  • Well... that's just Prime.
  • by Daath ( 225404 ) <lpNO@SPAMcoder.dk> on Wednesday November 14, 2001 @05:17PM (#2566155) Homepage Journal
    With these two projects you can help find cures for diseases like Alzheimers, Mad Cow even cancer!

    big project sponsored by university of oxford, NFCR and Intel

    Protein Folding@Home - basically the same, much smaller in scale though

    I run the one from UD on my windows desktop, and I run the folding@home client on my linux box :)
    • Oh please! You don't actually believe the hype you read do you? Chemist's can't even explain many of the properties of water, a teeny little molecule. If you think that (1) it is possible to simulate protein folding reliably and (2) there's actually a use for being able to do it then you're being deluded.


  • EFF Prize (Score:2, Informative)

    by Big Nate ( 229101 )
    The EFF webpage says that the big prize ($100,000) is to be awarded for a 10,000,000+ digit prime, so the $100,000 is probably still up for grabs (if you should feel so lucky).

    Granted, "greater than 3,500,000" could mean 10,000,000+ digits, but I don't think so...
  • I guess a good percentage of the readers have studied Eratosthenes of Cyrene [utah.edu], or at least his so-called "Sieve" to calculate primes. I'm wondering if anyone can outline how these larger numbers are found and validated?

    Big karma for some lucky geek, no doubt.

    • 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. [mersenne.org] But they're crappy.

      If you want a good faq about the math of the system, read the mailing list FAQ's [tasam.com]. These are much more interesting.
      • Actually, the methods they use to check the primes is not related to float arithmic. They use fast fourier transforms to speed-up the squaring required in the LL algorithm, with additional bonus that this FFT automatically performs the mod calculation.

        What one general idea behind prime checking is that there are several theorem's that you can use to show that a number is (probably) prime without checking all factors or using Erastostenes sieve. A few are given in faq: Q3.3. I believe one of those theorem's is Fermat's little theorem. These are not used in this program. Instead they use the LL test, based upon "For odd p, the Mersenne number 2^p-1 is prime if and only if 2^p-1 divides S(p-1) where S(n+1) = S(n)^2-2, and S(1)=4". The Fast Fourier transforms are used to calculate the S(n) with the modulo 2^p-1 part as a bonus.
  • It's great to see that Distributed.net is getting some work done. SETI's been around for years and they haven't found squat, which is particularly alarming since the damned things were given prime-time showings on CBS last night as well as releasing a new CD [mjifc.com].

  • GIMPS milestones (Score:2, Informative)

    by uigrad_2000 ( 398500 )
    The Great Internet Mersenne Prime Search keeps all the large milestones here:

    http://mersenne.org/status.htm [mersenne.org]

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

Mathemeticians stand on each other's shoulders while computer scientists stand on each other's toes. -- Richard Hamming