Matrices and Determinants

If $$1,$$ $$\omega ,{\omega ^2}$$ are the cube roots of unity, then \Delta = \left| {\matrix{ 1 & {{\omega ^n}} & {{\omega ^{2n}}} \cr {{\omega ^n}} & {{\omega ^{2n}}} & 1 \cr {{\omega ^{2n}}} & 1 & {{\omega ^n}} \cr } } \right| is equal to