#include "bits/stdc++.h"

using namespace std;
typedef long long ll;
const ll MOD = 1e9 + 7;
ll dp[1000001][3];
 int main() {
	 int N;
	 cin >> N;
	 dp[0][0] = 1;
	 for (int i = 0; i < N; i++) {
		 for (int j = 0; j <= 2; j++) {
			 if (j < 2) (dp[i + 1][j + 1] += dp[i][j]) %= MOD;
			 if (j > 0) (dp[i + 1][0] += dp[i][j]) %= MOD;
		 }
	 }
	 cout << (dp[N][0] + dp[N][1] + dp[N][2]) % MOD << endl;
}