whole lattice as expected, showing a clear contrast to the normal state. The $d$-wave nature appears in the negative sign of $D_{xy}(l)$ for $l
= 2 \sim 5$.

$U$-Dependence
--------------

The $U$-dependence of the energy gain in the SC state was shown in Fig. \[fig:DEg-U\]. with the same values of $N_s$ and $N_e$. The energy gain was determined from the depth of the minimum, as explained above. Except for the above-mentioned case of $U = 8$, the minimum position defined by optimal $\Delta$, $g$ and $\mu$ was determined by means of the correlated measurements and $E_g$ was calculated for this position with the same number of M. C. steps as for $U = 8$. Next, $E_g$ for $\Delta = 0.01$ was obtained and then the fitting parabola allowed to get the energy gain. The energy gain in this definition gives the condensation energy in the SC state in the present approximation. The energy gain has the maximum for about $U = 8$. It quickly decreases with decrease of $U$. It gradually decrease with increase of $U$ over 12. In contrast, the value of optimal $\Delta$ is nearly proportional to $U$ up to $U$ = 12 and then saturates for larger 