#include <iostream>
#include <algorithm>
#include <vector>
#include <map>
#include <string>
#include <numeric>
#include <cstring>
#define rep(i, n) for (int i = 0; i < (n); i++)

using ll = long long int;
using namespace std;

const int MOD = 1e9 + 7;

ll dp[1000010][3];
int N;

int main()
{
    dp[1][0] = 1;
    dp[2][1] = 1;
    dp[3][2] = 1;
    cin >> N;
    for (int i = 1; i < N; i++)
    {
        dp[i + 1][0] += (dp[i][1] + dp[i][2]) % MOD;
        dp[i + 2][1] += (dp[i][0] + dp[i][2]) % MOD;
        dp[i + 3][2] += (dp[i][0] + dp[i][1]) % MOD;
    }

    cout << (dp[N][0] + dp[N][1] + dp[N][2]) % MOD << endl;;


    return 0;
}