I've come upon the following question about the Fourier transformation
" Use $F_n x$ to determine the discrete Fourier transform of the vector $y=(x_0, x_2, ..., x_{2n-2})$ of the components of $x$ with even index"
The hint states that using the Fast Fourier transform factorisation splitting formula, but I haven't had any luck with it. Can someone please help me out?