ABSTRACT
In the 1700s, Leonhard Euler studied Pierre de Fermat's work on number theory and provided proofs for many of his statements. In addition, he gave a very useful generalization of Fermat's theorem. In 1770, Edward Waring wrote the book Meditationes Arithmeticae, in which he stated a property of prime numbers that his student John Wilson had discovered but neither Waring nor Wilson could prove. Henceforth, it has been known as Wilson's Theorem. However, the result was known to Bhaskara before Wilson, and also to Ibn al-Haytham and to Leibniz. The first published proof was by Lagrange in 1771. Wilson's theorem yields a primality test. Unfortunately, this test is not practical since there is no known method for computing factorials quickly.
