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#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

typedef unsigned long long l;
typedef vector<l> v_l;
typedef vector<v_l> vv_l;

vv_l P;


l find_best(l m, l n, v_l::iterator p_begin, v_l::iterator p_end){
    l best = m;
    l p = *p_begin;
    if (p_begin + 1 == p_end){
        return *(upper_bound(P[p].begin(), P[p].end(), n/m)-1) * m;
    }
    else{
        for(;m<n;m*=p){
            best = max(find_best(m, n, p_begin + 1, p_end), best);
        }
    }
    return best;
}
l brute_force(l k, l N, v_l p){
    l temp, min_rem, n;
    for(temp=N;;){
        n = temp;
        min_rem = 100;
        for(int i=0;i<k;){
           int rem = n % p[i];
           if(rem == 0){
               n /= p[i];
               continue;
           }
           if(rem < min_rem){
               min_rem = rem;
           }
           i++;
           if(n == 1){
               return temp;
           }
        }
        temp -= min_rem;
    }
}

int main(){
    l k, N;
    v_l p;
    cin >> k >> N;
    l temp;
    for(int i=0;i<k;i++){
        cin>>temp;
        p.push_back(temp);
    }
    // ALG
    for(int i=0;i<100;i++){
        v_l temp;
        P.push_back(temp);
    }

    for(int i=0;i<k;i++){
        l s = 1;
        l pp = p[i];
        P[pp].push_back(s);
        for(;pp <= N/s;s *= pp){
            P[pp].push_back(s);
        }
        P[pp].push_back(s);
    }
    if (k > 22)
        cout<<brute_force(k, N, p);
    else
        cout<<find_best(1, N, p.begin(), p.end())<<endl;
    return 0;
}