#include <iostream>
#include <vector>
using namespace std;
int main() {
	int n;
	cin >> n;
	vector<vector<vector<long long>>> dp(n + 1, vector<vector<long long>>(3, vector<long long>(2)));
	dp[0][0][0] = 1;
	for (int i = 1; i <= n; i++) {
		dp[i][1][0] = (dp[i - 1][0][1] + dp[i - 1][0][0]) % (long long)(1e9 + 7);
		dp[i][2][0] = dp[i - 1][1][0];
		dp[i][0][1] = (dp[i - 1][1][0] + dp[i - 1][2][0]) % (long long)(1e9 + 7);
	}
	int ans = 0;
	for (int i = 0; i < 3; i++)
		for (int j = 0; j < 2; j++)
			ans = (ans + dp[n][i][j]) % (long long)(1e9 + 7);
	cout << ans << endl;
}