#include<cstdio>
#include<iostream>
#include<algorithm>
#include<string>
#include<cstring>
#include<queue>
#include<vector>
#include<functional>
#include<cmath>
#include<map>
#include<stack>
#include<set>
#include<numeric>
#include<limits>
#include<iterator>

#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define rep(i,n) for(int i=0; i<n; i++)
#define FOR(i,a,n) for(int i=a; i<n; i++)

using namespace std;
typedef long long ll;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ll, char> plc;
typedef pair<string, string> pss;

int dp[1000010][3];
int mod = (int)(1e9 + 7);

int main()
{
	int n;
	cin >> n;

	dp[1][1] = 1;

	for (int i = 2; i <= n; i++) {
		dp[i][1] = dp[i - 1][0];
		dp[i][0] = dp[i - 1][1] + dp[i - 1][2];
		dp[i][0] %= mod;
		dp[i][2] = dp[i - 1][1];
	}

	cout << (((dp[n][1] + dp[n][0])%mod) + dp[n][2] )%mod<< endl;
	return 0;
}