#include <iostream>
#include <algorithm>
using namespace std;

int main(void) {
  constexpr int mod = int(pow(10, 9)) + 7;
  int n; scanf("%d", &n);
  vector<vector<int>> dp(4, vector<int>(n+1, 0)); // dp[4][n+1]
  // [前回の移動段数][今の段数] := パターン数
  dp[0][0] = 1;
  for(int i=0; i<n; ++i) {
    for(int prev=0; prev<=3; ++prev) {
      for(int curr=1; curr<=3; ++curr) {
        if(prev == curr) { continue; }
        if(i + curr > n) { continue; }
        dp[curr][i+curr] += dp[prev][i];
        dp[curr][i+curr] %= mod;
      }
    }
  }
  int res = 0;
  for(int prev=1; prev<=3; ++prev) {
    res += dp[prev][n];
    res %= mod;
  }
  printf("%d\n", res);
  return 0;
}