I am trying to recreate the following diagram for triangular numbers (smaller triangles within one larger triangle) using TikZ.
The colour is not important but white and grey is probably preferred.
I have tried to modify the code used here which produces a triangular grid but without success (I do not know how to produce more than one grid in a single figure and could not shade the triangles in the alternating pattern shown) and is the reason why I have not included any MWE.
Ideally the code would be flexible enough to choose the number of larger triangles required (6 are shown in the above figure).