Generate random numbers without repetition (or vanishing probability of repetition) without storing full list of past generated numbers?

I need to generate random numbers in a very large range, 128 bits integers, and I will generate a many many of them. I'll generate so many of them, that I cannot fit into memory a list of the numbers generated.

I also have the requirement that the generated numbers do not repeat, or at least that the probability of repetition is vanishingly small.

Is there an algorithm that does this?