#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1000500, MOD = 1e9 + 7;
int n, NFibo[MAXN];
int main() {
  NFibo[1] = 1;
  for (int i = (2); i < (int)(MAXN); i++)
    NFibo[i] = (NFibo[i - 1] + NFibo[i - 2] + 1) % MOD;
  while (scanf("%d", &n) >= 1) {
    printf("%d\n", (NFibo[n + 1] + MOD - 1) % MOD);
  }
  return 0;
}
