#include <bits/stdc++.h>
using namespace std;
const int maxn = 1111111;
const int maxm = 111;
const int INF = 0x3f3f3f3f;
int n, m, k;
int f[maxn];
int main() {
  scanf("%d", &n);
  f[0] = 0;
  f[1] = 1;
  for (int i = 2; i <= n; ++i) f[i] = (f[i - 1] + f[i - 2] + 2) % 1000000007;
  cout << f[n] << endl;
}
