#include <iostream>
 
using namespace std;
 
const int MOD = 1000000007;
 
long long power(long long x, long long y) {
    long long res = 1;
    x %= MOD;
    while (y > 0) {
        if (y & 1)
            res = (res * x) % MOD;
        y >>= 1;
        x = (x * x) % MOD;
    }
    return res;
}
 
int main() {
    int n;
    cin >> n;
 
    // Số lần chuyển đĩa
    long long result = (power(2, n) - 1 + MOD) % MOD;
 
    cout << result << endl;
 
    return 0;
}

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