#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
//#include<cctype>
#include<climits>
#include<iostream>
#include<string>
#include<vector>
#include<map>
//#include<list>
#include<queue>
#include<deque>
#include<algorithm>
//#include<numeric>
#include<utility>
#include<complex>
//#include<memory>
#include<functional>
#include<cassert>
#include<set>
#include<stack>

const int dx[] = {1, 0, -1, 0};
const int dy[] = {0, 1, 0, -1};
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef pair<int, int> pii;

const int MAXN = 1000010;
const ll MOD = 1e9+7;

ll dp[MAXN][3];

ll dfs(int n, int r) {
    ll& ret = dp[n][r];
    if (ret >= 0) return ret;
    if (n == 0) return 1;
    ret = 0;
    if (r+1 < 3) ret += dfs(n-1, r+1);
    if (r > 0) ret += dfs(n-1, 0);
    ret %= MOD;
    return ret;
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    int n;
    cin >> n;
    memset(dp, -1, sizeof(dp));
    cout << dfs(n, 0) << endl;
    return 0;
}