I ended up using a two-dimensional array, null-ing out irrelevant outliers and calculating subsequent rows and columns based on previous and next columns using each previous row. I decided to take multiple passes (loops) at massaging the data in each cell in order to make the logic a bit more straightforward. Here’s what I ended up with:
I decided to add some parameters to make things interesting and to display the triangle on the page instead of logging to console to make it look better. I wouldn’t be surprised to find a better and more efficient way of doing this – that is the very nature of programming.