$\lambda^i_s$ is the multiplier for constraint $s$, $s=0,1,\ldots,S$.
for all $s$ and $l$, $D_{sl}U^i(x^i)-\lambda^i_sp_{sl}=0$.
for all $j$, $-\lambda^i_0q_j+\sum_s\lambda^i_sa^j_s=0$.
The Radner budget constraint must be satisfied.
$x^i\gg0$ and $\lambda^i\gg0$.