#include <iostream>
#include <sstream>
#include <string>
#include <vector>
#include <functional>
#include <tuple>
#include <climits>
#include <algorithm>
#include <queue>
#include <unordered_map>
#include <unordered_set>
#include <set>
#include <iomanip>

using namespace std;

int N;
vector<vector<int>> dp;

uint64_t solve(int index, int ken)
{
    if(ken>=3)
        return 0;
    if(index==N)
        return 1;
    if(dp[index][ken] != -1)
        return dp[index][ken];

    uint64_t a=0, b=0;
    if(ken!=0)
        a = solve(index+1, 0); // パ
    b = solve(index+1, ken+1);
    dp[index][ken] = (a+b)%(1000000000+7);
    return dp[index][ken];
}

int main()
{
    cin >> N;
    dp.resize(N);
    for(auto &a : dp)
        a.resize(3,-1);
    cout << solve(0, 0) << endl;
}