Nikon patent for 18mm f/1.8, 20mm f/1.8 FX lenses | Nikon Rumors
And the 24 f1.4 N = 36 f1.4 N on DX. It is a 16 = 24 DX that is missing! The longer Nikon goes without one, the more people will buy a Sony E mount camera with their 16 f2.8 = 24 equiv. (admittedly not a good lens, distorts a lot) or a Panasonic / Olympus...