Thanks for the suggestion.  You are right about *x*, *n*, or *a* being the best possible parameter name.   That said, it doesn't seem to have ever caused a problem in practice (this API has been around for a very long time), so I'm reluctant to create any disruption (breaking existing code) with a deprecation for something with so little benefit (this docstrings are very clear about what the parameter means).  There is also the matter of possible confusion with the seed() method which uses the *a* or the internal _randommodule.c that uses *n* but doesn't allow keyword arguments).

I think the lesson here is that parameter names should be carefully considered when a new API is created rather than decades after its release into the wild.