1. FIGURATE NUMBERS By: Amber Y. Precal 5 th Hour

2. What is a Figurate Number????  Figurate numbers are sequences generated by figures made up of evenly spaced dots.  Figurate numbers include the triangular numbers, square numbers, pentagonal numbers, etc. Sometimes they are called polygonal numbers if they form regular polygons.

3. Some Types of Figurate Numbers  Triangle  Square  Polygonal  Hexagonal  Pentagonal

4. Triangular Figurate Numbers It can be represented in the form of a triangular grid of points where the first row contains a single element and each row to follow contains one more element than the previous one.

5. Square Figurate Numbers A square number, also called a perfect square, is a figurate number of the form, where n is an integer. For example the square numbers for, 1,... are 0, 1, 4, 9, 16, 25, 36, 49,...

6. Polygonal, Hexagonal, and Pentagonal Polygonal is a generalization of triangular, square,etc., figurate numbers A polygonal number and it goes in the form of 6. The first few are 1, 6, 15, 28, 45,... A polygonal number that goes in the forms of 5. 1, 5, 12, 22…

7. Who Invented Figurate Numbers? The Pythagoreans invented Figurate Numbers in the 18 th century. This type of number was also called looping.