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#include <iostream>
#include <algorithm>
#include <unordered_set>

int main() {
  int k; long long int N;

  std::cin >> k;
  std::cin >> N;

  int primes[k];
  for(int i = 0; i < k; i++) {
    std::cin >> primes[i];
  }
  std::sort(primes, primes+k);

  long long int max = 1;
  std::unordered_set<long long int> composites;
  composites.insert(1);
  long long int divided;

  for (int i = 2; i <= N; i++) {
    for(int j = 0; j < k; j++) {
      divided = i/primes[j];
      if (i%primes[j] == 0 && composites.find(divided) != composites.end()) {
        composites.insert(i);
        max = i;
      }
    }
  }

  std::cout << max;
  return 0;
}