#include <bits/stdc++.h>
using namespace std;
int y[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
int ly[12] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
double distance(int a, int b) {
  double c, d, dis;
  c = pow((double)a, 2);
  d = pow((double)b, 2);
  dis = sqrt(c + d);
  return dis;
}
bool cmp(int a, int b) { return a > b; }
string ssort(string a) {
  sort(a.begin(), a.end());
  return a;
}
long long int fib[1000007], ans;
int main() {
  long long int n;
  cin >> n;
  fib[0] = 0;
  fib[1] = 1;
  for (long long int i = 2; i <= n + 3; i++) {
    fib[i] = (fib[i - 1] + fib[i - 2]) % 1000000007;
  }
  ans = (fib[n + 3] - 2) % 1000000007;
  cout << ans << endl;
  return 0;
}
