  The space $M_{\mu/i,j}$ spanned by all partial derivatives of the lattice
polynomial $\Delta_{\mu/i,j}(X;Y)$ is investigated in math.CO/9809126 and many
conjectures are given. Here, we prove all these conjectures for the $Y$-free
component $M_{\mu/i,j}^0$ of $M_{\mu/i,j}$. In particular, we give an explicit
bases for $M_{\mu/i,j}^0$ which allow us to prove directly the central {\sl
four term recurrence} for these spaces.
