13th root of a 100 digit number...

[transplant99]

FRANKFURT, Germany -- A 38-year-old with degrees in psychology, education and computer science set a record by needing only 11.8 seconds to calculate the 13th root of a 100-digit number in his head. Onlookers with electronic calculators needed more time to solve the problem that Gert Mittring figured on his own, with two umpires checking the time.

"I first think of an elegant problem-solving algorithm and the result comes immediately," said Mittring, who beat the previous record of 13.55 seconds, set by Frenchman Alexis Lemaire in 2002.


Wow.

[arsenal]

Same guy also calculated the 23rd root of a 200 digit number in 40.83 seconds.
Math Record Holders (not updated)

I know who to calculate the square root of a number.. how do you calculate the nth root of a number? I am not sure if this was covered in high school math, and if it was, I don't remember.

Does this look right for all you math wizards out there:

Log(large_number_here) / nth_number
ie:
large_number = 20,000,000,000,000
nth_number = 13

Log(20,000,000,000,000)/13
Feel as though something is missing..

[kermitology]

yeah, that basically boils down to (10^13)*(log 2)/13. If you're dealing with numbers like that it would be easy, if it was something more compilcated.. as in not a power of 10, it would be harder.

[Maritime Q-Scout]

to answer your question

... never