Barycentric refinement

In unit 19, we look at the problem to compute the number of vertices edges, and faces of a Barycentric refinement of an icosahedron. Here we see the first 2 Barycentric refinements. We have for the original icosahedron x=(v,e,f) = (12, 30, 20), then for the refinement Ax=(62, 180, 120) and for the next refinement A² (362, 1080, 720). The matrix A is

| 1 1 1 |
| 0 2 6 |
| 0 0 6 |