Implement the χ function used in the nonlinear part of SHA-3 and Xoodyak

[rusydi]

The χ function over n-dimensional vector space over GF(2) is defined as χ(x_{0}, x_{1}, ..., x_{n-1}) = (y_{0}, y_{1}, ..., y_{n-1}) where

y_i = x_i + (x_{i+1} + 1) x_{i+2}

for i=0, 1, ..., n-1 and the indices are computed modulo n