Do you mean that given finite resources (like time and matter) we would be unable to express the number? Or are you talking about a sort of recursive thing whe

Do you mean that given finite resources (like time and matter) we would be unable to express the number? Or are you talking about a sort of recursive thing where writing down a number which is a sum of all natural numbers up to and including itself is impossible since that number is bigger each time you look at it?