#define _USE_MATH_DEFINES
#define _CRT_SECURE_NO_WARNINGS
#include "bits/stdc++.h"
#define rep(i,n) for(int i = 0;i < n;i++)
#define REP(i,n,k) for(int i = n;i < k;i++)
#define P(p) cout<<(p)<<endl;
#define pi 3.1415926535
using namespace std;
typedef long long ll;
int dx[] = { 0, 1, 0, -1 };
int dy[] = { -1, 0, 1, 0 };

unsigned long long sttoi(std::string str) {
	unsigned long long ret;
	std::stringstream ss; ss << str;
	ss >> ret;
	return ret;
}
string s;
ll k1[1000001], k2[1000001], p[1000001];
void solve() {
	k1[1] = 1;
	k2[1] = 0;
	p[1] = 0;
	ll n;
	cin >> n;
	for (int i = 2; i <= n; i++){
		k1[i] = p[i - 1] % 1000000007;
		k2[i] = k1[i - 1] % 1000000007;
		p[i] = k1[i - 1] % 1000000007 + k2[i - 1] % 1000000007;
		k1[i] %= 1000000007;
		k2[i] %= 1000000007;
		p[i] %= 1000000007;
	}
	P((k1[n] + k2[n] + p[n])%1000000007);
}

int main() {
	solve();
	return 0;
}