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#include <iostream>
#include <algorithm>

using namespace std;
typedef long long ull;

int main() {
    cin.sync_with_stdio(false);
    cin.tie(nullptr);
    int k;
    ull n;
    cin>>k>>n;
    short primes[k];
    for (short i = 0; i < k; i++) {
        cin>>primes[i];
    }
    sort(primes, primes+k);

    ull temp = n, max;
    for (ull i = n; i > 0; i--) {
        max = 1;
        temp = i;
        for (int j = k-1; j >= 0; j--) {
            while (temp % primes[j] == 0) {
                temp /= primes[j];
                max *= primes[j];
            }
            if (temp == 1) {
                cout<<max;
                exit(0);
            }
        }
    }

    cout<<max;

    return 0;
}