[Math] An example of a bounded countably infinite subset of the real numbers.

Question

I've been trying to think of an example of bounded, countably infinite subset of the real numbers. However, knowing that countably infinite means can be put into 1-1 correspondence with the naturals, this doesn't seem intuitively obvious.

Thanks in advance.

Answer 1

$$\left\{\frac1n:n\in\Bbb Z^+\right\}$$