#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll mod = 1e9 + 7;
ll dp[1000001][3] = {};

int main()
{
	ll N;
	cin >> N;
	dp[1][0] = 1; dp[2][1] = 1; dp[3][2] = 1; dp[3][0] = dp[3][1] = 1;
	for (int i = 4; i <= N; i++) {
		dp[i][0] = (dp[i - 1][1] + dp[i - 1][2]) % mod;
		dp[i][1] = (dp[i - 2][0] + dp[i - 2][2]) % mod;
		dp[i][2] = (dp[i - 3][0] + dp[i - 3][1]) % mod;
	}
	cout << (dp[N][0] + dp[N][1] + dp[N][2]) % mod << endl;
	return 0;
}