I've looked at these links already;
which gave an answer for earlier versions of Mathematica. Yet when I try to input either OmegaPrime or OmegaPrimePi, and then hit enter, I don't get any numbers. I have tried using N[OmegaPrime] to force a number. It's as if the functions have been removed in version 9.0 . And someone mentioned using PrimeOmega, so I tried that and N[PrimeOmega]. I would also like to know if version 10.0 has a higher Prime[n] so I can decide on whether to upgrade.