It doesn't seem to be that difficult, but it's doing my head in. I want to calculate the saturation ampere turns for a gapped ferrite core, but I don't get credible answers! I can calculate the effective permeability using the effective core length and the gap length, and my AL figure (nH per turns-squared) matches the manufacturer's data if I use the following equation:

AL = perm-zero * perm-effective / core factor

The only trick here is to be careful to work in mm or in m

Is this the same factor to convert ampere turns into tesla?