Dear list, I have implemented a preliminary version of \fp_factorial:n and \fp_gamma:n The current working precision of \fp_gamma:n is limited to 1e-11. So far, error checking for the argument of factorial is missing and I don't know how to integrate this into l3fp, especially making these available in \fp_eval:n as factorial(x) and gamma(x). If anyone would be so kind as to provide some guidance, I would be very grateful. Cheers, Henri