Covariance using formula is not the same as "actual" covariance? I have a matrix $\mathbf{Y}$ (as you will see below) and I am trying to compute its covariance. However, explicitly using the covariance formula (note that $\mathbf{C}$ is centered so the meanY disappears from the formula) gives another result than when using the CovarianceMatrix command from Maple as illustrated here  gives.

You should be dividing by $n-1 = 7$, not by $n=8$.