Let $$T = \{9^k : k ~ \mbox{is an integer}, 0 \le k \le 4000\}$$. Given that $$9^{4000}_{}$$ has $$3817$$ digits and that its first (leftmost) digit is $$9$$, how many elements of $$T_{}^{}$$ have $$9$$ as their leftmost digit?

(第八届AIME1990 第13题)