#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll mod = 1e9 + 7;
int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	ll n;
	cin >> n;
	vector<vector<ll>>dp(n + 4, vector<ll>(4, 0));
	dp[1][0] = 1;
	dp[2][1] = 1;
	dp[3][0] = 1;
	dp[3][1] = 1;
	dp[3][2] = 1;
	for (ll i = 4; i <= n; i++) {
		dp[i][0] = dp[i - 1][1] + dp[i - 1][2];
		dp[i][0] %= mod;
		dp[i][1] = dp[i - 2][0] + dp[i - 2][2];
		dp[i][1] %= mod;
		dp[i][2] = dp[i - 3][1] + dp[i - 3][0];
		dp[i][2] %= mod;
	}
	ll val = dp[n][0] + dp[n][1] + dp[n][2];
	while (val < 0) {
		val += mod;
	}
	cout << val % mod << endl;
}