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#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
using namespace std;
int k, p[30];
long long n, res;
int s;
int tab[900000], ts;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cin >> k >> n;
  s = sqrt(n)+5;
  for (int i=1; i<=k; i++) cin >> p[i];
  sort(p+1, p+k+1);
  vector<int> dp_set, rest;
  for (int i=1; i<=k; i++)
      dp_set.push_back(p[i]);
  reverse(dp_set.begin(), dp_set.end());
  // vector<int> prev = {1}, next;
  bool twos = false;
  if (dp_set.back() == 2) {
    dp_set.pop_back();
    twos = true;
  }
  tab[ts++] = 1;
  for (int p: dp_set) {
    long long pp = p;
    int os = ts;
    vector<int> ends = {ts};
    while (pp <= s) {
      long long highest = s / pp;
      int ms = ts;
      // int size = 0;
      // for (int j=0; j<prev.size() && prev[j] <= highest; j++) size++;
      // int oldsize = next.size();
      // next.resize(oldsize+size);
      for (int j=0; j<os && tab[j] <= highest; j++)
        tab[ts++] = tab[j] * pp;
      ends.push_back(ts);
      pp *= p;
    }
    for (int i=0; i<ends.size()-1; i++)
      inplace_merge(tab, tab+ends[i], tab+ends[i+1]);
    // prev.clear();
    // prev.swap(next);
    // cerr << p << ": " << ts << endl;
  }
  
  // if (twos) dp_set.push_back(2);
  // int start = ts-1;
  for (int t=0; t<=(twos?60:0); t++) {
    if ((n>>t) == 0) break;
    res = max(res, (1LL<<t));
    // long long high = n >> t;
    // while (tab[start] > high) start--;
    while (tab[ts-1] * (long long)tab[ts-1] > (n>>t)) ts--;
    for (long long p: dp_set) {
      int i = ts-1;
      // if (t == 16) cerr << "p = " << p << endl;
      if (p > (n>>t)) continue;
      p <<= t;
      long long v = n / p;
      for (int j=0; j<ts; j++) {
        long long x = tab[j];
        while (i >= 0 && x * tab[i] > v) i--;
        if (i < 0) break;
        res = max(res, x * tab[i] * p);
      }
    }
  }
  cout << res << "\n";
  return 0;
}