#include <bits/stdc++.h>
#include<iostream>
#include<iomanip>
#include<string>
#include<algorithm>
#include<vector>
#include<set>
#include<list>
#include<queue>
#include<math.h>
#include<bitset>
using ll = long long;
using namespace std;

int main()
{
    ll n, grc = 1, grd = 1, gt;
    cin >> n >> gt;
    for (int i = 1; i < n; i++){
        ll t1, t2, g;
        cin >> t1;
        t2 = t1;
        g = gcd(gt, t1);
        gt /= g;
        t1 /= g;
        grc *= t1;
        grd *= gt;
        gt = t2;
    }
    cout << grc << "/" << grd << endl;
}