6
/ pi*I -pi*I \
| ---- ------|
| 3 3 |
\- e + e /
1 - --------------------
6
/ -pi*I pi*I\
| ------ ----|
| 3 3 |
\e + e /
-----------------------------------------------
2 4
/ pi*I -pi*I \ / pi*I -pi*I \
| ---- ------| | ---- ------|
| 3 3 | | 3 3 |
\- e + e / \- e + e /
1 + -------------------- + --------------------
2 4
/ -pi*I pi*I\ / -pi*I pi*I\
| ------ ----| | ------ ----|
| 3 3 | | 3 3 |
\e + e / \e + e /
$$\frac{1 - \frac{\left(- e^{\frac{i \pi}{3}} + e^{- \frac{i \pi}{3}}\right)^{6}}{\left(e^{- \frac{i \pi}{3}} + e^{\frac{i \pi}{3}}\right)^{6}}}{1 + \frac{\left(- e^{\frac{i \pi}{3}} + e^{- \frac{i \pi}{3}}\right)^{4}}{\left(e^{- \frac{i \pi}{3}} + e^{\frac{i \pi}{3}}\right)^{4}} + \frac{\left(- e^{\frac{i \pi}{3}} + e^{- \frac{i \pi}{3}}\right)^{2}}{\left(e^{- \frac{i \pi}{3}} + e^{\frac{i \pi}{3}}\right)^{2}}}$$
$$4$$