#include <iostream>
#include <vector>
#include <string>
#include <iomanip>

using namespace std;

typedef long long LL;

int main(){
    int N;
    cin >> N;
    double base = 1.0;
    for(int i = 0; i < 5; i++){
        base *= (double)(N-i)/(99-i);
    }
    cout << setprecision(13) << base * 12 << endl;

    return 0;
}