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

int n, p = 1e9 + 7;

int ksm(int x, int n) {
	int ans = 1, base = x;
	while (n) {
		if (n&1) (ans *= base) %= p;
		(base *= base) %= p;
		n >>= 1;
	}
	return ans % p;
}

signed main() {
	freopen("magic.in", "r", stdin);
	freopen("magic.out", "w", stdout);
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	cin >> n;
	cout << (ksm(3, n + 1) - 1) * ksm(2, p - 2) % p;
	return 0;
}