[Wilson's Theorem][1] [1]: https://en.wikipedia.org/wiki/Wilson%27s_theorem According to Wikipedia: > This theorem was stated by Ibn al-Haytham (c. 1000 AD) and in the 18th > century, by John Wilson. Edward Waring announced the theorem in > 1770, although neither he nor his student Wilson could prove it. > Lagrange gave the first proof in 1771. There is evidence that > Leibniz was also aware of the result a century earlier, but he never > published it.