#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n);i++)
#define sz(x) int(x.size())
typedef long long ll;
typedef pair<int,int> P;

const int mod = 1e9+7;

int dp[1000010][4]; 

int main(){
  int n;
  cin >> n;
  dp[0][0] = 1;
  rep(i,n) rep(j,4) {
    for (int k = 1; k < 4; k++) if (k != j) {
      (dp[i+k][k] += dp[i][j]) %= mod;
    }
  }
  int res = 0;
  rep(i,4) {
    (res += dp[n][i]) %= mod;
  }
  cout << res << endl;
  return 0;
}