Use the standard closed three-strand braid , a four-crossing diagram of the figure-eight knot. The diagram has two positive and two negative crossings, so .
Figure 1.
Four-crossing closed braid for the figure-eight knot, with three starting meridians
. Details.
We calculate its Kauffman bracket, making the inversion symmetry explicit rather than merely asserting amphichirality.
In the Temperley-Lieb diagram algebra on three strands put , . The relations are , , , . The bracket image of one two-crossing block is
Closing planar diagrams gives the bracket trace on the three-strand Temperley-Lieb algebra:
These values follow because the closures have respectively three, two and one circles. Expanding and reducing gives
Taking its trace and substituting yields
There is no writhe correction, so
The equality is immediate from the five displayed coefficients. The same braid model supplies the meridians used in part (d).