PolygonalNumber

Polygonal number (WMA)


PolygonalNumber[n]

gives the n-th triangular number.

PolygonalNumber[r, n]

gives the n-th r-gonal number.

The sum of two consecutive Polygonal numbers is the square of the larger number:

PolygonalNumber[r, n] can be interpreted as the number of points arranged in the form of n-1 polygons of r sides.

List the tenth r-gonal number of regular polygons from 3 to 8:

See also Binomial, and RegularPolygon.

Multinomial
RogersTanimotoDissimilarity