Editing Polygonal number (section)

{{Short description|Type of figurate number}}
In [[mathematics]], a '''polygonal number''' is a [[Integer|number]] that counts dots arranged in the shape of a [[regular polygon]]{{r|tattersall2005|p=2-3}}. These are one type of 2-dimensional [[figurate number]]s.

Polygonal numbers were first studied during the 6th century BC by the Ancient Greeks, who investigated and discussed properties of [[Pronic number|oblong]], [[Triangular Number|triangular]], and [[Square number|square numbers]]{{r|tattersall2005|p=1}}.