Augustus the Strong, Elector of Saxony, later King of Poland and Grand Duke of Lithuania (1670-1733), supposedly had 365 illegitimate children (and one legitimate child, a son).
So he knew how to multiply. How fast, I don't know. If spread out evenly over his adult life that would be only about 9 kids a year.
How did that legitimate one slip through the cracks there?
Augustus the Strong must have had trouble doing the math when trying to keep track of all those offspring. He could have done that math a bit faster if he had just had more fingers and toes to work with...
