Recursive set

Have you ever played a game of "telephone" with your friends, where you whisper a message to the person next to you, and then they whisper it to the next person, and so on? A recursive set is like that game of telephone, but instead of a message, it's a set of numbers.

Let's say we have a set of numbers: {1, 2, 3}. Now, we can use a formula to create a new set of numbers based on the first set. The formula is:

- Take each number in the original set and add one to it.
- Put those new numbers into a new set.

So, if we apply this formula to our first set ({1, 2, 3}), we get a new set: {2, 3, 4}.

But we can keep going! We can take that new set ({2, 3, 4}) and apply the same formula to it:

- Take each number in the set and add one to it.
- Put those new numbers into a new set.

So, if we do that, we get another new set: {3, 4, 5}.

We can keep doing this over and over again, which is why it's called "recursive". Each new set we create is based on the previous set we made. And the sets themselves are called "recursive sets".

To summarize, a recursive set is like playing a game of telephone with sets of numbers, where each new set is created by applying a formula to the previous set.