Dating from 1,000 years before Pythagoras's theorem, the Babylonian clay tablet is a trigonometric table more accurate than any today, say researchers. At least 1,000 years before the Greek mathematician Pythagoras looked at a right angled triangle and worked out that the square of the longest side is always equal to the sum of the squares of the other two, an unknown Babylonian genius took a clay tablet and a reed pen and marked out not just the same theorem, but a series of trigonometry tables which scientists claim are more accurate than any available today. The 3,700-year-old broken clay tablet survives in the collections of Columbia University, and scientists now believe they have cracked its secrets. The team from the University of New South Wales in Sydney believe that the four columns and 15 rows of cuneiform - wedge shaped indentations made in the wet clay - represent the world's oldest and most accurate working trigonometric table, a working tool which could have been used in