1716.Singer House

Time Limit: 1s Memory Limit: 256MB

It is known that passages in Singer house are complex and intertwined. Let's define a Singer k-house as a graph built by the following process: take complete binary tree of height k and add edges from each vertex to all its successors, if they are not yet present. 1716_1.png Singer 4-house Count the number of non-empty paths in Singer k-house which do not pass the same vertex twice. Two paths are distinct if the sets or the orders of visited vertices are different. Since the answer can be large, output it modulo 109+7.

Input Format(From the terminal/stdin)

Input The only line contains single integer k (1 \le k \le 400).

Output Format(To the terminal/stdout)

Output Print single integer- the answer for the task modulo 109+7.

Sample Input 1

Copy
2
 \n

Sample Output 1

Copy
9
 \n

Sample Input 2

Copy
3
 \n

Sample Output 2

Copy
245
   \n

Sample Input 3

Copy
20
  \n

Sample Output 3

Copy
550384565
         \n

Hints

There are 9 paths in the first example (the vertices are numbered on the picture below): 1, 2, 3, 1-2, 2-1, 1-3, 3-1, 2-1-3, 3-1-2. 1716_2.png Singer 2-house

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