Slight error in Exponential Growth and the Legend of Paal Paysam

by AlanM
(Charlottesville, VA, USA)

This sentence is incorrect
"On the fortieth square the king would have had to put 1,000,000,000 grains of rice."

To be correct it should read:

"On the thirieth square the king would have had to put 1,000,000,000 grains of rice."

or

"On the fortieth square the king would have had to put 1,000,000,000,000 grains of rice."