We consider dissections of regular -gons into triangles by diagonals which do not intersect inside the -gon. A bicoloured triangulation is such a dissection of an -gon in which each triangle is coloured black or white and any two triangles which share an edge have different colours. We call a positive interger triangulable if every regular -gon has a bicoloured triangulation such that for each vertex of the -gon the number of black triangles of which is a vertex is greater that the number of white triangles of which is a vertex.
Find all triangulable numbers.
Find all triangulable numbers.