Arthur Benjamin is one "human calculator" that i have actually watched over the years. I can't remember exactly, but my parents bought a series of videos called the "great courses" made by Arthur. They bought these videos to help my brother in his math class. This is when i first saw him. I then later saw him on some TED videos. http://www.youtube.com/watch?v=e4PTvXtz4GM. In these videos he demonstrates his insane ability to calculate huge multiplication problems. He calls his form of math "mathemagic." In these TED videos he usually asks his audience to give him a number with a certain number of digits. He then asks for another number with a certain number of digits and he is able to perform the multiplication of the numbers much faster than a calculator could. He also takes the square roots of up to 5 digit numbers and thinks out loud as he calculates the answer. Until he is asked to calculate numbers above 4 digits, Arthur always beats a calculator. Arthur also shows off in this particular TED video by demonstrating his knowledge on birthdays. He asks the audience for their birthdate and is able to give them the exact day of the week they were born. He takes his knowledge to another level by asking a volunteer to give him a random date between 1600 and 3000 (future). The volunteer gives the date 2730 on June 13; Arthur tells him that that will be a friday within 3 seconds. He probably is not the most famous mathematician. But Arthur Benjamin certainly blows my mind apart. He has a lot of videos on youtube where he provides math tricks that we can use in our every day life. http://www.youtube.com/watch?v=ZvzsWmUqDF4.
Arthur Benjamin has been a professor at Harvey Mudd College since 1989. He is my favorite mathematician because he is so knowledgeable and also provides a lot of math help. He really helped my brother out in calculus and i hope i still have his tapes because he is a very good teacher. EUS!
http://en.wikipedia.org/wiki/Arthur_T._Benjamin
