import sys sys.stdin = open("input.txt", "r") sys.stdout = open("output.txt", "w") n = int(input()) c = [None for i in range(n+1)] for i in range(1, n, 2): c[i] = 0 c[2] = 1 c[0] = 1 def recursion(n, c): if c[n] != None: return c[n] kkk = 0 for i in range(1, n): kkk += recursion(i-1, c) * recursion(n-i-1, c) c[n] = kkk return kkk print(recursion(n, c))