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

#define RREP(i,s,e) for (i = s; i >= e; i--)
#define rrep(i,n) RREP(i,n,0)
#define REP(i,s,e) for (i = s; i < e; i++)
#define rep(i,n) REP(i,0,n)
#define INF 1e8

typedef long long ll;

int main() {
    int i, n;
    double ans = 1;
    cin >> n;
    cout << fixed << setprecision(7);
    if (n < 5)
        cout << 0 << endl;
    else {
        double x = 99;
        rep (i,5) {
            ans *= n--;
            ans /= x--;
        }
        cout << 12*ans << endl;
    }
    return 0;
}