#include <iostream>
#include <fstream>
#include <cstdio>
#include <cmath>
#include <vector>
#include <cstring>
#include <string>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <algorithm>
using namespace std;

#define REP(i,n) for(int i=0; i<n; ++i)
#define FOR(i,a,b) for(int i=a; i<=b; ++i)
#define FORR(i,a,b) for (int i=a; i>=b; --i)
#define ALL(c) (c).begin(), (c).end()

typedef long long ll;
typedef vector<int> VI;
typedef vector<ll> VL;
typedef vector<VI> VVI;
typedef pair<int,int> P;
typedef pair<ll,ll> PL;

const ll mod = 1e9 + 7;

ll dp[1000010][4];

int main() {
	int n;
	cin >> n;
	dp[0][0] = 1;
	REP(i,n) REP(j,4){
		FOR(k,1,3){
			if (k == j) continue;
			dp[i+k][k] = (dp[i+k][k] + dp[i][j]) % mod;
		}
	}
	ll ans = 0;
	FOR(j,1,3) ans = (ans + dp[n][j]) % mod;
	cout << ans << endl;

	return 0;
}