tetraktys
A triangular figure consisting of ten points arranged in four rows, with one, two, three, and four points in each row. It is a geometrical representation of the fourth triangular number. (Tressider, 2000)
A triangular figure consisting of ten points arranged in four rows, with one, two, three, and four points in each row. It is a geometrical representation of the fourth triangular number. (Tressider, 2000)