#include <iostream>
#include <vector>
using namespace std;
const long long MOD = 1000000007;
int main(){
	int N;
	cin >> N;
	vector<vector<long long>> dp(3, vector<long long>(N + 1, 0));
	dp[0][1] = 1;
	if (N >= 2){
		dp[1][2] = 1;
	}
	if (N >= 3){
		dp[2][3] = 1;
	}
	for (int i = 1; i <= N; i++){
		for (int j = 0; j < 3; j++){
			for (int k = 0; k < 3; k++){
				if (j != k && i - (j + 1) >= 0 && i + (k + 1) <= N){
					dp[k][i + k + 1] += dp[j][i];
					dp[k][i + k + 1] %= MOD;
				}
			}
		}
	}
	cout << (dp[0][N] + dp[1][N] + dp[2][N]) % MOD << endl;
}