Online text recognition models have improved a lot in the past few years, because of improvements in model structure and also because of bigger datasets. Mathematical expression (ME) recognition is a more complex task that has not received as much attention. However, the problem is different from text recognition in a number of interesting ways which can prevent improvements on one transfering to the other. Though MEs share with text most of their symbols, they follow a more rigid structure which is also two-dimensional. Where text can be treated to some extent as a one-dimensional problem amenable to sequence modeling, MEs cannot, because the relative position of symbols in space is meaningful.