N = int(input())
mod = 10 ** 9 + 7
dp = [[0] * (N + 5) for i in range(4)]
dp[0][0] = 1
for i in range(N):
    for j in range(4):
        for k in range(1, 4):
            if j == k:
                continue
            dp[k][i + k] += dp[j][i]
            dp[k][i + k] %= mod
ans = 0
for i in range(4):
    ans += dp[i][N]
print(ans%mod)