An enupla is an ordered sequence of **no** Elements. It is also known as **n-double**, **n-tuple** or simply **tuple**.

When n = 2, we can call the sequence double. For example, (1,2) is a double. Already the sequence (-2, 1) is another double.

Therefore, what differs a number from a set is that:

- An enuple can contain an object more than once.

- Objects are necessarily represented in the given order.