2nπ−π32 n \pi-\frac{\pi}{3}2nπ−3π
2nπ+π32 n \pi+\frac{\pi}{3}2nπ+3π
n˙π+(−1)nπ6\dot{n} \pi+(-1)^{n} \frac{\pi}{6}n˙π+(−1)n6π
2nπ+(−1)nπ32 n \pi+(-1)^{n} \frac{\pi}{3}2nπ+(−1)n3π