#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define mod 1000000007

int main()
{
        ll n, fd, tmp_fd, fa, tmp_fa, fb, tmp_fb, fc, tmp_fc;
        fd = 0, fa = fb = fc = 1;
        cin >> n;
  
        for (ll i = 2; i <= n; i++)
        {

                tmp_fd = fd;
                fd = (fa + fb + fc) % mod;
                tmp_fa = fa;
                fa = (tmp_fd + fb + fc) % mod;
                tmp_fb = fb;
                fb = (tmp_fa + tmp_fd + fc) % mod;
                tmp_fc = fc;
                fc = (tmp_fa + tmp_fb + tmp_fd) % mod;
        }
        cout << fd;
}