What are reactangle numbers?

Rectangular numbers are a type of figurate number that represent the number of dots that can form a rectangle. Specifically, a rectangular number can be expressed as the product of two consecutive positive integers, ( n(n + 1) ), where ( n ) is a positive integer. For example, the first few rectangular numbers are 2 (1x2), 6 (2x3), and 12 (3x4). They can also be visualized as arrays of dots that can be arranged into a rectangle.