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Math Whiz Breaks Calculation Record
keyshawn632 writes "The Associated Press reports that Gert Mittring, 38, needed only 11.8 seconds to calculate the 13th root of a 100-digit number in his head at a math museum in Giessen, a small town, located in western Germany.
It's worth noting though that his feat will not be recognized by The Guinness Book Of World Records because of the difficulty of standardizing such mathematical challenges."
I can't even read 100 digits in 30 seconds.
"I'm not talking to myself, I'm just the only one who's listening." - Jimmies Chicken Shack
Just memorize the 13th root of every 100-digit number in existence. Sheesh.
Obligitory Family Guy quote:
Lois: Peter, why would they make you presidesnt?
Peter: Maybe it's because I can recite all 50 states in a quarter of a second - RARF!
Lois: Peter, that was just a loud yelping noise
...Mittring will now go for the record of longest lifespan without losing one's virginity.
you misspelled "forty-two".
Just as I read this article, what would start playing in my playlist but Mr. Roboto. I wonder if he has parts made in Japan?
Does it hurt to hear them lying? Was this the only world you had?
The book itself was an interesting read, and at the time I just ate it up. It has a lot of tricks regarding number theory, mathematical riddles, calendar tricks, and calculation of pi, for example. It teaches how to figure the day of the week for any Gregorian date of any time in a few seconds, a trick which I still remember and use today!
As for the Pi, it contained a few poems and sayings whose letter counts signified the individual digits. I started trying to memorize pi, with my sights set firmly on the world record (as I am not without my own mathematical and mnemonic prowess). However, around grade 9, I decided to abandon my quest in order to get a life. I had memorized 1350 digits at that point.
One such quote held little significance for me at the time, but has since become hilarious. "How I want a drink, alcoholic of course, after the heavy chapters involving quantum mechanics!" Needless to say, my quantum prof found it quite funny. :)
"Name a state. Within a second, I'll tell you the capital of it."
"Wisconsin"
"W."
"Derp de derp."
I think a better joke would be.
And that would be the only rooting this guy will ever do in his life
it is only after a long journey that you know the strength of the horse.
Get this guy some sappho juice.
Unless there is some really trivial algorithm for finding 13th roots I totally call bullshit. If it takes him four seconds to memorize a 22 digit number how can he manipulate and find a 13th root for a 100 digit number in just over twice that amount of time?
There has to be a trick to it aside from "thinking really fast"
Tom
Someday, I'll have a real sig.
It's worth noting though that his feat will not be recognized by The Guinness Book Of World Records because of the difficulty of standardizing such mathematical challenges.
That's the problem when dealing with a highly subjective field like mathematics.
Probably breaking codes for some government or another. Someone with talent with numbers and such will catch the eye of someone out there. Could it be that this was just to show off his talent as a sort of "job interview"? Probably not, but I expect he will get some calls about it anyway.
Gert Mittring was disqualified when judges noted a small sticker on his chest in a post-event checkup. It was discovered that he had Intel Inside.
The news set off a legal feeding frenzy. SCO sued Mr. Mittring for using the company's super secret 13th root finder source code. Microsoft then added to the man's woes by suing for patent infringement over Microsoft's patents on 100 digit numbers. RIAA then sued him for including "8675309" in the answer -- obviously a stolen clip from "Jenny" by Tommy Tutone.
Two wrongs don't make a right, but three lefts do.
I read somewhere that you only need about 50 digits of pi to describe a circle the size of the observable universe to within the diameter of a proton, let alone a chocolate donut.
This isn't to say that 1350 digits wouldn't be useful! If you ever wake up in an alternate universe (you were warned about operating quantum machinery while drunk!) just look up pi in a math book. The degree of trouble you're in could correlate to the digit at which your memorized value, and the local value of pi, diverge.
If pi only diverges after 1000 or more digits, you're probably alright, except for having to re-memorize pi.
If pi diverges after 100 digits, there may be some minor historical divergences, like, say, President Nixon being impeached, or Bush winning a second term. The mind boggles!
If pi diverges after 30 or 40 digits, look out the window. Do dinosaurs roam the earth? Since you're surrounded by ruthless, math-book-publishing carnivores, consider donating yourself to the primate house of the zoo.
If local pi begins with a number other than 3, you should start to get worried, or maybe implode.
I can do the 23rd root of a 163 digit number in 5.8 seconds, and I wasn't even trying. I've climbed Mt. Everest in an hour and a half. I can rewrite the Linux kernel in under an hour. I can count up to ten thousand coins in no more than a minute.
And yet, curiously, it takes me almost...-checks watch- five minutes to make a stupid, useless post on /. Strange eh?
To fight the war on terror, stop being afraid.
I don't remember if this was the same guy I saw on TV. But the guy I saw was performing large multiplications and finding large roots in front of an elementary school class. They later showed doctors or scientists doing brain imaging on him while he solved math problems. What they found was that he was using parts of his brain that most people utilize during visualization (not sure how they were able to separate it from him actually seeing something). He said he visualizes the number in his head and then he can perform various manipulations on them and he can "see" the math work itself out. Obviously some is probably genetic, but he also commented on practicing his methods for 5-7 years. He also appears to not be the only root master.
And how much about the problem did he know in advance? Did he know it would be a 13th root of a 100-digit number? Did he know that the number would be a perfect 13th power of an integer? I find it impossible to believe he calculated a 13th root of a 100-digit number in 11.8 seconds without knowing any of these things. Knowing all of them makes the problem a lot easier.
The 13th root of a 100-digit number will always have 7 digits. If you memorize the first few digits of the 13th powers of numbers between 49 and 58 and you are given a 100-digit number, then you immediately know the first 2 digits of the 13th root. Memorize the initial digits of 13th power of numbers between 491 and 588 and you immediately know the first 3 digits. By memorizing the terminal digits of 13th powers of numbers less than 100, you could similarly immediately get the last 3 digits. That leaves 1 digit to compute, which is a slightly less impressive-sounding feat for 11.8 seconds. It's not a trivial calculation, though, and not at all shabby for 11.8 seconds.
Jonathan
That leaves you with a mere... 7,193,306 possible roots to memorize.
I don't know how they do it, but I am familiar with modulo-10 math "tricks". For example, did you know that if you add up the individial digits in any number and the result is divisible by 3, then the original number is divisible by 3? For example "621". 6+2+1=9, and so 621 is divisible by 3 (Try it: 621/3=207).
13th root has similar magic: the 13th root of any number will have the same last digit as the number you are trying to take the root of. For example, the 13th root of 2235879388560037062539773567 is 127. Notice that they both end in 7. An integer and its 13th power always ends in the same digit. Try it.
The point is, that little trick itself reduces the problem space by a factor of 10 right there. So I'm assuming they've studied and learned further tricks like these. Ask them for the 11th root of the same number and they'll probably come up completely blank.
First, figure out the "year number". This part -- and the month number -- take some practice. Here's the first few to get you started:
1900 - 0
1904 - 5
1908 - 3
1912 - 1
1916 - 6
1920 - 4
1924 - 2
1928 - 0
And it repeats thusly. Note that the "year number" starts at 0 for the beginning of the century, and is decreased by two (modulo seven) every leap year.
In case you're interested in the other 75% of the time, simply add one to the year number for every year you add. Thus, 1901 becomes 1, 1902 becomes 2, etc.
The "month" number requires memorization of another table, which cannot be recalculated as quickly as the year number:
Jan - 0
Feb - 3
Mar - 3
Apr - 6
May - 1
Jun - 4
Jul - 6
Aug - 2
Sep - 5
Oct - 0
Nov - 3
Dec - 5
Add the month number to the year number. If your year is a leap year and your month is January or February, subtract 1.
Next, add the day number. The day number is the day. :P
Now, add or subtract sevens as necessary until you end up with a number between 0 and 6:
0 - Sunday
1 - Monday
2 - Tuesday
3 - Wednesday
4 - Thursday
5 - Friday
6 - Saturday
The result will be the day of the week.
If your desired date does not begin with a "19", you have to add a century number as well. I believe 2000 is a leap year, since every 100 years is not but every 400 years is. Thus, the century number of 2000 is 6 (or, equivalently, -1). 1800 is 5, 1700 is 3, etc. (I am not certain of these.)
As an example, today's year number is 5, the month number is 3, and the day number is 24. After compensating for the century by subtracting 1, we obtain 31. This reduces to 3 (by subtracting 28), which corresponds to Wednesday. Since it is Wednesday, and since I am in a large empty room, I further deduce that the lecture has ended.
Well, I guess that's not so outrageous depending on the precision you need. All the 43rd roots of 100 digit numbers are greater than 200 and less than 212, so if you only need integer precision you only have 13 choices. And memorizing 12 thresholds is not that hard.
The 13th root of a 100-digit number is an 8-digit number. Here's how YOU can find TWO of those 8 digits in an instant.
1. The leading digit is ALWAYS 4.
2. The last digit of the 13-th root of N is always the same as the last digit of N.
(The first fact follows because Floor[N[(10^100 - 1)^(1/13)]] = 49238826 and Floor[N[(10^99 - 1)^(1/13)]] = 41246263. The second holds because N^13 is congruent to N modulo 10.)
With minimal practice, you can get the second-highest digit from the magnitude. Beyond that I can only speculate what he's doing. But by taking an alternating sum of the digits, you get its value mod 11, which gives you the value of the root mod 11, which buys you another digit. Now you're halfway there...
Are described here. Rest of the site is also informative and insane.
http://racine13eme.site.voila.fr/100digang.htm
-pvg
Does anyone have a math book I can borrow? I really need to look something up.
I roomed with a guy in college who would calculate a 10 digit by 10 digit multiplication in his head throughout the day on weekends. He would be grilling or watching TV and you would see him get him and write down 1 digit of his answer.
In grade school he had memorized 52 decks of shuffled cards in some insane short period of time. The teacher would ask him what the 12th card of the 17 deck was... and he would start listing them forward and backward from there.
We often went to the casinos with him. He would card count and we just would bet whatever he would bet. We would all make a $100 or so and leave. He was always afraid of getting caught.
Some government agency approached him for running sets of numbers from point a to point b. They liked the fact that he could just put all those digits in his head without a papertrail.
Last I heard of him, he was avoiding math as much as possible... he enrolled in some DO program in a medical school somewhere. Numbers came too easy for this guy... and he knew he would go crazy if he went into a math field.
So now he's a doc somewhere. Probably calculating 10 by 10 digit numbers in his head as he examines you...