

We are commonly taught that organic molecules have (2n-the number of meso compounds it forms)possible stereoisomers, where n = the total number of stereocenters. In organic chemistry a stereocenter is a tetrahedral atom with four different groups.
This works great with some molecules. Below is a simple example of a molecule with two stereocenters. It has two total stereocenters and three stereoisomers, because one of its stereoisomers is meso. Example - 2^2-1 = 3
