#define _USE_MATH_DEFINES
#include <cstdio>
#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <complex>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <limits>
#include <climits>
#include <cfloat>
#include <functional>
#include <iterator>
using namespace std;

const int MOD = 1000000007;

int main()
{
    int n;
    cin >> n;

    vector<vector<int> > dp(n+3, vector<int>(4, 0));
    for(int i=1; i<=3; ++i)
        dp[i][i] = 1;
    for(int i=1; i<n; ++i){
        for(int j=1; j<=3; ++j){
            for(int a=1; a<=3; ++a){
                if(j != a){
                    dp[i+a][a] += dp[i][j];
                    dp[i+a][a] %= MOD;
                }
            }
        }
    }

    int ans = 0;
    for(int i=1; i<=3; ++i){
        ans += dp[n][i];
        ans %= MOD;
    }
    cout << ans << endl;

    return 0;
}