and the point is the h of the next layer is always able to look at everything in front of it including its own its own H basically it's the one layer down its own position one layer down while the G is only allowed to look at the a it's allowed to look at the ages but the H is from before right so so all the G's here are only ever able to look at the H is from before the current position whereas the H is always allowed here to look at the same but also at the H at the current position and now at the last layer you simply ask