Give you two definitions tree and rooted tree. An undirected connected graph without cycles is called a tree. A tree is called rooted if it has a distinguished vertex r called the root. Your task is to make a program to calculate the number of rooted trees with n vertices denoted as Tn. The case n=5 is shown in Fig. 1.

There are multiple cases in this problem and ended by the EOF. In each case, there is only one integer means n(1<=n<=40) .

For each test case, there is only one integer means Tn.

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