#include <bits/stdc++.h>
#define bp __builtin_popcountll
#define pb push_back
#define in(s) freopen(s, "r", stdin);
#define inout(s, end1, end2) freopen((string(s) + "." + end1).c_str(), "r", stdin),\
		freopen((string(s) + "." + end2).c_str(), "w", stdout);
#define fi first
#define se second
#define bw(i, r, l) for (int i = r - 1; i >= l; i--)
#define fw(i, l, r) for (int i = l; i <= r; i++)
#define fa(i, x) for (auto i: x)
using namespace std;
const int mod = (119 << 23) + 1, inf = 1061109567;
const long long infll = 4557430888798830399;
const int N = 1e5 + 5;
int n, a[N];
signed main() {
	#ifdef BLU
	in("blu.inp");
	#endif
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
	cin >> n;
	fw (i, 1, n) cin >> a[i];
	sort(a + 1, a + n + 1);
	int ans = 1;
	fw (i, 0, n - 1) ans *= __gcd(i, a[i + 1]);
	cout << ans; 
	return 0;
}