MOD = 10 ** 9 + 7
n = int(input())
dp = [[0] * 10 for _ in range(n + 1)]
for i in range(1, n + 1):
    dp[i][1] = 1
    for j in range(1, 10):
        dp[i][j] += dp[i - 1][j] + dp[i][j - 1]
        dp[i][j] %= MOD
        
print((sum(dp[-1]) + 1) % MOD)