Hello everyone. I figured some members may find this entertaining and interesting. Arthur Benjamin does a great job here; he does miss (722)^2 and (457)^2, but he's still awesome.
Benjamin
Here are some books if you are interested in mental calculation:
Smith, Steven B. The Great Mental Calculators: The Psychology, Methods, and Lives of Calculating Prodigies Past and Present. New York: Columbia University Press, 1983.
Benjamin, Arthur and Shermer, Michael. Secrets of Mental Math: The Mathemagician's Guide to Lightning Calculation and Amazing Math Tricks. USA: Three Rivers Press, 2006.
Benjamin
Here are some books if you are interested in mental calculation:
Smith, Steven B. The Great Mental Calculators: The Psychology, Methods, and Lives of Calculating Prodigies Past and Present. New York: Columbia University Press, 1983.
Benjamin, Arthur and Shermer, Michael. Secrets of Mental Math: The Mathemagician's Guide to Lightning Calculation and Amazing Math Tricks. USA: Three Rivers Press, 2006.