import sys

sys.setrecursionlimit(10**6)
int1 = lambda x: int(x)-1
p2D = lambda x: print(*x, sep="\n")
def II(): return int(sys.stdin.buffer.readline())
def LI(): return list(map(int, sys.stdin.buffer.readline().split()))
def LI1(): return list(map(int1, sys.stdin.buffer.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def BI(): return sys.stdin.buffer.readline().rstrip()
def SI(): return sys.stdin.buffer.readline().rstrip().decode()
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
inf = 10**16
# md = 998244353
md = 10**9+7

n=II()
dp=[[0]*(n+1) for _ in range(2*n+1)]
dp[0][0]=1
for i in range(2*n):
    for j in range(n+1):
        if (i+j)&1:continue
        pre=dp[i][j]
        if pre==0:continue
        l=(i+j)//2
        if l<n:dp[i+1][j+1]+=pre
        if j-1>=0:dp[i+1][j-1]+=pre

# p2D(dp)
print(dp[-1][0])