#define _USE_MATH_DEFINES
#include <algorithm>
#include <cstdio>
#include <functional>
#include <iostream>
#include <cfloat>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <time.h>
#include <vector>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> i_i;
typedef pair<ll, int> ll_i;
typedef pair<double, int> d_i;
typedef pair<ll, ll> ll_ll;
typedef pair<double, double> d_d;
struct edge { int u, v; ll w; };

ll MOD = 1000000007;
ll _MOD = 1000000009;
double EPS = 1e-10;

int main() {
	int N; cin >> N;
	vector<vector<int> > dp(N + 1, vector<int>(3));
	dp[0][0] = 1;
	for (int i = 0; i < N; i++)
		for (int j = 0; j < 3; j++) {
			if (j) dp[i + 1][0] = (dp[i + 1][0] + dp[i][j]) % MOD;
			if (j + 1 < 3) dp[i + 1][j + 1] = (dp[i + 1][j + 1] + dp[i][j]) % MOD;
		}
	int sum = 0;
	for (int j = 0; j < 3; j++)
		sum = (sum + dp[N][j]) % MOD;
	cout << sum << endl;
}