Given a $N \times N$ matrix $A$ (it has structure, specifically it is a real-valued Vandermonde matrix if that helps) from which the first $L \ll N$ columns are taken to form $\tilde{A}$.
Now the inverse Gram matrix of $\tilde{A}$ is formed:
$$ G = \left(\tilde{A}^T \tilde{A}\right)^{-1} $$
Is there any meaningful relation or expression to exploit between either:
- entries of $A$
- entries of $A^{-1}$
- Determinant of $A$
and/or
- G
- $\operatorname{Tr}(G)$
?