Mathematics Throughout HistoryThe Creation of Zero and Pi |
How was the value of pi determined arithmetically? |
One of the earliest mathematical formulas for pi was determined by English mathematician John Wallis (1616–1703), who wrote the notation as:

Another more commonly-recognized notation for pi is often attributed to German philosopher and mathematician Baron Gottfried Wilhelm Leibniz (1646–1716), but is more likely the work of Scottish mathematician James Gregory (1638–1675):

Both are amazing examples of something that was not only figured out using geometric methods, but also arithmetic methods.