Which of the following is equivalent to ∑k=0n−1ωk2\sum_{k=0}^{n-1} \omega^{k^2}∑k=0n−1ωk2 where ω=ei2π/n\omega = e^{i2\pi/n}ω=ei2π/n and n=3n=3n=3?
000
111
ω\omegaω
ω2\omega^2ω2