Given a list of real numbers, as in the Cantor argument, give details on how to construct three different real numbers that are not on the list.
Do you need to find the three numbers in one or several lifetimes? If several, then you can find the first one, add it as the first element to the list and then repeat the process.
Also, are numbers written in decimal or in binary? If in decimal, then you have several way of choosing a different digit.