940 Mathematics: Born Abu'l-Wafa al-Buzjani. Wrote several treatises using the finger-counting system of arithmetic, and was also an expert on the Indian numerals system. About the Indian system he wrote: "[it] did not find application in business circles and among the population of the Eastern Caliphate for a long time." [1] Using the Indian numeral system, abu'l Wafa was able to extract roots.