Rectangular numbers are a subset of composite numbers. The squares of prime numbers will be composite but not rectangular.
The second and third rectangular numbers are 6 and 12
rectangular numbers are numbers just displayed in the shape of a rectangle e.g take the number 6 it can be shown as: ** ** or ****** **
There is no such formula. Rectangular numbers are composite numbers and there is no known formula that will generate either composite numbers or prime numbers.
So far I know that 120 is a rectangular number
Rectangular numbers are of the form n(n+1) for n = 1, 2, 3, 4, 5, 6, ... The first few rectangular numbers are: 2, 6, 12, 20, 30, 42, ...
A row of numbers, a column of numbers or a rectangular layout of numbers.
They are simply rectangular arrays of numbers.