Slashdot Mirror
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."
Just memorize the 13th root of every 100-digit number in existence. Sheesh.
...Mittring will now go for the record of longest lifespan without losing one's virginity.
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.
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.
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.
Of course, to be fair, it should be noted that the above poster is a postdoc lecturer at MIT who is teaching Mathematics for Computer Science this semester and wrote the course notes, including a substantial portion involving number theory.
Oh God, now that I think about it . . . you're putting this on the final, aren't you? NOoOOOooOooOoOOoO!!!!!