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Pi Recited to 100,000 Digits

Posted by ryuzaki0 on from the three-point-one-what dept.

DiAmOnDirc writes "Akira Haraguchi, 60, needed more than 16 hours to recite the number to 100,000 decimal places, breaking his personal best of 83,431 digits set in 1995, his office said Wednesday. He made the attempt at a public hall in Kisarazu, just east of Tokyo. Haraguchi, a psychiatric counselor and business consultant in nearby Mobara city, took a break of about 5 minutes every one to two hours, going to the rest room and eating rice balls during the attempt, said Naoki Fujii, spokesman of Haraguchi's office. Fujii said all of Haraguchi's activities during the attempt, including his bathroom breaks, were videotaped for evidence that will later be sent for verification by the Guinness Book of Records."

12 of 335 comments (clear)

  1. Details by rjstanford · · Score: 4, Interesting

    More to the point (although you could infer it from the "newsworthiness" of the story): he did it from memory. Although I'd be surprised if anyone had ever even read out 100,000 digits of Pi but, then again, I've been surprised by stupid people. Also from the article, "In 2002, University of Tokyo mathematicians, aided by a supercomputer, set the world record for figuring out pi to 1.24 trillion decimal places." So:

    a) He's got a way to go; and
    b) Sagan not proven right yet, still no circle.

    I'm guessing there's no girlfriend, either, but the only evidence I have supporting this is that, well, this guy memorized 100,000 digits of Pi. C'mon...

    --
    You're special forces then? That's great! I just love your olympics!
    1. Re:Details by pilkul · · Score: 4, Interesting
      Now, he must be the only man who can remember (or not) the birthdays of his parents and girlfriends (if he has any)...
      Not necessarily. Memorizing large amounts of random information has more to do with effective mnemonic techniques and capacity for intense concentration than base retentive skill. If he doesn't concentrate on something, he still can forget it. I've heard from people who like to memorize decks of cards that it's a cool party trick but it's a good idea not to let your girlfriend know you can do it for just this reason!
    2. Re:Details by 1u3hr · · Score: 2, Interesting
      More to the point (although you could infer it from the "newsworthiness" of the story): he did it from memory.

      You could "infer" it from the meaning of the word "recite".

      recite. To repeat or utter aloud (something rehearsed or memorized).

    3. Re:Details by RzUpAnmsCwrds · · Score: 2, Interesting
      Sagan not proven right yet, still no circle.


      Technically, since Pi is infinitely long and never repeats, any finite series of digits must appear at some point. The first 100 million digits of Pi, for example, contain most every 7-digit phone number. Of course, the longer the string you want to find, the further you have to go. But that's not really a problem.
  2. He's using memory technique by zymano · · Score: 3, Interesting

    He's not memorizing like a regular person would.

    It's been talked about on slashdot before using some memorization technique association groups of numbers with memorable patterns.

    Don't ask me for links.

    1. Re:He's using memory technique by gkwok · · Score: 3, Interesting

      Poe, E.: Near a Raven encodes the first 740 digits of pi using word lengths as digits, while preserving the structure, story, and tone of the poem it is based on.

    2. Re:He's using memory technique by Galvatron · · Score: 3, Interesting
      One of the oldest and most venerable general-purpose mneumonic techniques is called simply The Art of Memory, which basically involves memorizing a particular path through a particular building, and then populating that mental building with objects and symbols based on whatever one is trying to remember. In an age before cheap paper and writing utensils, this was very widely used, though rarely written about, and is likely responsible for much of the West's obsession with symbolism and dual meanings (the cournicopia as a symbol of plenty, Mars and Venus representing masculinity and femininity, the whole art of heraldry, the assignment to each saint of a particular profession, etc.). Indeed, Freemasonry, that most symbolic of institutions, owed some of its broad popularity, and its shift in focus from an operative guild to a speculative fraternity, to its connection with the Art of Memory.


      I imagine that this guy was probably using a more specialized mneumonic, like the Raven poem linked to by the guy above, but as the Wikipedia link mentions, many of those who perform great feats of memory do still use this. Let's admit it though: there is no extant trick which would make memorizing 100,000 digits EASY.

      --
      "The question of whether a computer can think is no more interesting than that of whether a submarine can swim" -EWD
  3. Of course... by Mad_Rain · · Score: 1, Interesting

    Akira Haraguchi [...] a psychiatric counselor

    So I guess being able to recite pi to the 100,000 digit is just further evidence that he's crazy.

    --
    "What do you think?" "I think 'What, do you think?!'"
  4. Easy way to remember pi to 8 decimal places by Fish+(David+Trout) · · Score: 5, Interesting

    I'm sure we can all remember the first digit: 3, right?

    But it's all those digits (decimal places) that follows the 3 that we all have trouble remembering, right?

    So okay. Just memorize the following simple phrase:

        "I wish I could recollect pi easily today"

    The number of letters in each word are the first 8 decimal digits:

            1 4 1 5 9 2 6 5

    Thus PI is approximately: 3.14159265...

    Which should be <i>plenty</i> long enough for most calculations.

    The only hard part of course is remembering to use the word "recollect" instead of "remember". :)

    --
    "Fish" (David B. Trout)
  5. Re:That's very impressive... by rolfwind · · Score: 3, Interesting

    Sure, Olympic Runners can run fast, but what is the point? Any car made in the last 100 years can go faster.

    Sure, in the days of hunting/gathering, it was a vital skill. Transportation, for me, is a means to an end, but if you have no place to go, why even bother with it at all?

  6. Just 1 digit more accuracy ... how about 3 or 4 by Skapare · · Score: 5, Interesting

    OK, so you really meant 355/113. The value of that fraction is actually accurate to 7 digits, which is 1 digit more than how it is expressed in whole fraction form. But if you look further, you can find a fraction that has an accuracy that is 3 digits more than the total number of digits in the fraction. That fraction is (with digits chopped so it doesn't get mangled in Slashdot HTML):

    1901870728 5669230760 9014394471 4770339621 5907683135 4633719252 6115562704 3396809635 6432000780 8107929370 2997523451 8768883574 1387003036 8533612856 7115805986 7702399073 2279944269 0522019469 9766118756 0590556190 3648850292 8002591

    ... divided by ...

    6053842551 4642032610 2361023215 9405317163 9147815034 5020739231 2531721347 4068823247 6946000058 7137745497 9656144746 8267746412 8740227175 4410094658 7144148739 6268034351 3347328160 6663121381 1257617460 3015134435 3855924025 288111

    That's 217 numerator digits and 216 denominator digits for a total of 433 digits that gives PI to 436 digits. It doesn't get any better until a fraction with 14593 digits in both numerator and denominator for a total of 29186 digits that gives PI to an accuracy of 29190 digits, 4 more digits than in the fraction.

    But 355/113 is easier to remember and 355/133 is apparently easier to type :-)

    --
    now we need to go OSS in diesel cars
  7. Re:Rice by Gwwfps · · Score: 3, Interesting

    A whole ball could actually hold at least a few thousand digits if not more. In a lot of places in China (usually near tourist attractions), there are artists who write your requested messages on rice. After some googling, I could only find these two pretty bad photos. The first seems to be not as good as most I've actually seen, the second just shows an artist working. Another one can give one a real idea of what the masters can do: 42 US presidents on rice.