Swarm of Polygons

There is a regular n-gon. Some points are marked on each of its sides. There are x1 point marked on the first side, x2 – on the second, …, xn – on the nth. The marked points do not coincide with the vertices of the n-gon. You can choose no more than one of the marked points from each side and form a convex non-degenerate polygon by connecting all those points with lines. Now your task is to find t