#include <bits/stdc++.h>
using namespace std;
const int N = 1e6 + 5, mod = 1e9 + 7;
int n;
long long dp[N];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  dp[1] = 1;
  dp[2] = 2;
  for (int i = 3; i < N; i++) {
    dp[i] = (dp[i - 1] + dp[i - 2]) % mod;
  }
  cin >> n;
  cout << (dp[n + 2] - 2 + mod) % mod;
}
