#include <iostream>
using namespace std;

uint64_t dp[1000010][3];
const uint64_t mod = 1000000007;

int main() {
  int n;
  cin >> n;

  for (int i = 0; i < 3; i++) {
    dp[0][i] = 0;
  }

  dp[1][0] = dp[1][2] = 0;
  dp[1][1] = 1;

  for (int i = 1; i < n; i++) {
    dp[i + 1][0] = (dp[i][1] + dp[i][2]) % mod;
    dp[i + 1][1] = dp[i][0] % mod;
    dp[i + 1][2] = dp[i][1] % mod;
  }

  cout << (dp[n][0] + dp[n][1] + dp[n][2]) % mod << endl;

  return 0;
}