#include<iostream>
#include<cstdio>
#include<cstring>
#include <cstdlib>  
#include <math.h>
#include <cmath>   
#include<cctype>
#include<string>
#include<set>
#include<iomanip>
#include <map>
#include<algorithm>
#include <functional>
#include<vector>
#include<climits>
#include<stack>
#include<queue>
#include <deque>
#include <climits>
#include <typeinfo>
#include <utility> 
#define all(x) (x).begin(),(x).end()
#define rep(i,m,n) for(int i = m;i < n;++i)
#define pb push_back
#define fore(i,a) for(auto &i:a)
#define rrep(i,m,n) for(int i = m;i >= n;--i)
#define INF INT_MAX/2
using namespace std;
using ll = long long;
using R = double;
using Data = pair<ll, vector<int>>;
const ll MOD = 1e9 + 7;
const ll inf = 1LL << 50;
struct edge { ll from; ll to; ll cost; };

ll dp[1010101][3];

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

	dp[1][0] = 1;
	dp[2][1] = 1;
	dp[3][0] = 1;
	dp[3][1] = 1;
	dp[3][2] = 1;

	rep(i, 4, n + 1) {
		dp[i][0] = dp[i - 1][1] + dp[i - 1][2];
		dp[i][1] = dp[i - 2][0] + dp[i - 2][2];
		dp[i][2] = dp[i - 3][0] + dp[i - 3][1];
		dp[i][0] %= MOD;
		dp[i][1] %= MOD;
		dp[i][2] %= MOD;
	}
	
	cout << (dp[n][0] + dp[n][1] + dp[n][2]) % MOD << endl;

	return 0;
}