Hi, I'm currently following this lecture: Here is the script I downloaded up to the point were I got lost: It seems to be a simple combinatorics problem looking for the possible combinations of the N subsystems for a given set of occupation number n_i (how many subsystems are in state i). But then there comes this diagram, which I don't understand. What does "State" on the x-axis say? How can it be "narrowed on the scale of N"? I find the lecture hard to follow as it is not really well structured. Maybe I missed an important point there.