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#include <algorithm>
#include <iostream>
#include <iterator>
#include <vector>
using namespace std;

namespace {

template <typename T, typename F>
void generate(vector<int> const& primes, T m, F&& f, T x=1, int i=0)
{
  if (!f(x)) return;
  int k = primes.size();
  while (i < k) {
    auto p = primes[i];
    if (x > m / p) break;
    generate(primes, m, f, x * p, i);
    ++i;
  }
}

long long solve(vector<int> primes, long long m)
{
  sort(primes.begin(), primes.end());

  vector<int> primes1, primes2;
  int k = primes.size();
  for (int i = 0; i < k; ++i) {
    if (i < 5) primes1.emplace_back(primes[i]);
    else primes2.emplace_back(primes[i]);
  }

  vector<long long> small; small.reserve(300000);
  generate(primes1, m, [&](long long x) {
    small.emplace_back(x);
    return true;
  });

  sort(small.begin(), small.end());

  long long res = 0;

  generate(primes2, m, [&](long long x) {
    auto y = m / x;
    if (x * y <= res) return false;
    auto it = lower_bound(small.begin(), small.end(), y + 1);
    if (it != small.begin()) {
      auto it2 = prev(it);
      res = max(res, x * *it2);
    }
    return true;
  });

  return res;
}

}

int main()
{
  iostream::sync_with_stdio(false);
  cin.tie(nullptr);

  int n;
  long long m;
  cin >> n >> m;

  vector<int> primes(n);
  for (int& p: primes) cin >> p;

  cout << solve(move(primes), m) << endl;

  return 0;
}