Carbon Nanotube Trefoil Knot (CNTTK)

Carbon Trefoil knot? Is it possible to have a carbon nanotube curved like a trefoil knot or even bizarrer like a torus knot (CNTTK)?
Chuang has discovered a systamatic scheme to generate correct structures for a large family of CNTTR in his Ms thesis recently. Preliminary semi-empirical calculations based on AM1 show that these molecules could be quite stable. Of course, this doesn't mean it is straightforward to synthesize them.
In the following figure, I show the smallest stable carbon trefoil knot together with the famous woodcut of trefoil knot by Escher.
I believe that this kind of carbon torus knot have never been mentioned before, let along the efforts to find out the correct arrangement of nonhexagons on the tubule surface.