Press the green flag. Use turbo mode. Type in "pxa" or "pxb" in the "number of points" to use a preset. Or type in a number, 3<x<10. 2 and 1 work but are pointless. (line and dot). 3 points with factor 30 is the Sierpinski triangle.
Wikipedia :-) Also, apparently, lakshay has done the f:30/60 version with 4 points some time ago. http://beta.scratch.mit.edu/projects/10128936/