Triangle
Triangulation refers to the total number of objects used to make the triangle when a triangle is made of a certain object. For example, when you create a triangle over four lines, the total number of objects in the list becomes 10, and 10 becomes one of the triangles. The nth triangular number N is the sum of the natural numbers from 1 to n, where n must be a natural number due to the definition of the triangular number. The sequence of triangles is 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 78, 91, 105, 120 ..., There is a theorem that all natural numbers can be expressed as a sum of up to three triangles, which Karl Friedrich Gauss proved in 1716. This theorem is a case of Fermat's multidimensional theorem that all natural numbers can be expressed as the sum of the maximum number of angular numbers.