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

int main() {
    int N;
    cin >> N;
    vector<int64_t> A(N);
    map<int64_t, int> mp;
    for (int i = 0; i < N; ++i) {
        cin >> A[i];
        mp[A[i]]++;
    }
    sort(begin(A), end(A));
    int64_t num = 1, den = 1;
    for (int i = 0; i < N; ++i) {
        num *= mp[A[i]]--;
        den *= (N - i);
    }
    den /= gcd(num, den);
    cout << den << endl;
}