This is the tree made by Wacław Sierpiński. When the flag is clicked, it will ask you if you want to choose your level of the tree. If you pick yes, you get to choose your level. If you say no, it will select a random level. And if you click reset, it will reset the tree.
P.S. You shouldn't go above level 7, otherwise it will crash because it will be too much detail, even with turbo mode.