#include <algorithm>
#include <cmath>
#include <cstdio>
#include <deque>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <vector>

using namespace std;

typedef long long ll;

#define MOD 1000000007

int main() {
  int n;
  cin >> n;
  vector<vector<ll> > dp(n + 1, vector<ll>(3));
  dp[1][1] = 1;
  for (int i = 2; i <= n; ++i) {
    dp[i][0] = (dp[i][0] + dp[i - 1][1]) % MOD;
    dp[i][0] = (dp[i][0] + dp[i - 1][2]) % MOD;
    dp[i][1] = (dp[i][1] + dp[i - 1][0]) % MOD;
    dp[i][2] = (dp[i][2] + dp[i - 1][1]) % MOD;
  }
  ll ans = 0;
  for (int i = 0; i <= 2; ++i) {
    ans = (ans + dp[n][i]) % MOD;
  }
  cout << ans << endl;
  return 0;
}