In exercise [1, p. 34 exercise 2.8] we are asked to find the inverse of the  n\times n hermitian matrix \mathbf{R} given by [1, (2.27)] by recursively applying Woodbury’s identity. This should be done by considering the cases where f_{1},f_{2} are arbitrary and where f_{1}=k/n, f_{2}=l/n for k,l beeing distinct integers in the range \left[ -n/2,n/2-1 \right] for n even and \left[ -(n-1)/2,(n-1)/2 \right] for n odd. read the conclusion >