#include <iostream>
#include <algorithm>

using namespace std;
const int MOD = 1e9 + 7;


int dp[1000001][4];
int main()
{
    int n;
    cin >> n;

    dp[0][0] = 1;

    for(int i = 0; i < n; i++)
    {
        for(int j = 0; j < 4; j++)
        {
            for(int k = 1; k < 4; k++)
            {
                if(k != j)
                    dp[i + k][k] += dp[i][j] % MOD;
            }
        }
    }

    int ans = 0;
    for(int i = 0; i < 4; i++)
        ans += dp[n][i] % MOD;

    cout << ans << endl;
}