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#include <bits/stdc++.h>
using namespace std;
#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
  enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge {c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef LOCAL
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
    *this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
#else
sim dor(const c&) { ris; }
#endif
};
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

typedef long long ll;

//~ const ll T = 1000;
//~ const ll BIL = T * T * T;

//~ bool isPrime(ll n) {
	//~ for(ll i = 2; i * i <= n; ++i)
		//~ if(n % i == 0)
			//~ return false;
	//~ return true;
//~ }

//~ ll r() {
	//~ return rand() * ((ll) RAND_MAX + 1) + rand();
//~ }

//~ bool yes(ll n, vector<int> primes) {
	//~ for(int p : primes)
		//~ while(n % p == 0)
			//~ n /= p;
	//~ return n == 1;
//~ }

const int MAGIC = 1e6 + 5; // 4MB
int small[MAGIC];
const int MAX_MEMO = 251419; // 2MB
int cnt_memo;
ll memo[MAX_MEMO + 5];
ll answer = 1;

void consider(ll maybe) {
	answer = max(answer, maybe);
}

void findSmall(const vector<int> & primes) {
	small[1] = 1;
	for(int i = 1; i < MAGIC; ++i) {
		if(small[i]) {
			for(int p : primes) {
				if(i * p < MAGIC)
					small[i * p] = i * p;
				else
					break;
			}
		}
		else small[i] = small[i-1];
	}
}

void rec(int i, ll cur, const vector<int> & primes, const ll up_to, bool firstTurn) {
	assert(cur <= up_to);
	
	ll should = up_to / cur;
	if(should < MAGIC) {
		consider(cur * small[should]);
		return;
	}
	
	if(i == (int) primes.size()) {
		if(firstTurn) {
			assert(cnt_memo < MAX_MEMO);
			memo[cnt_memo++] = cur;
		}
		else {
			should = up_to / cur;
			int which = upper_bound(memo, memo + cnt_memo, should) - memo;
			if(which != 0)
				consider(cur * memo[which - 1]);
		}
		return;
	}
	
	while(cur <= up_to) {
		rec(i + 1, cur, primes, up_to, firstTurn);
		if(up_to / primes[i] < cur)
			cur = up_to + 1;
		else
			cur *= primes[i];
	}
}

int main() {
	int cnt_primes;
	ll N;
	cin >> cnt_primes >> N;
	vector<int> primes(cnt_primes);
	for(int & p : primes)
		cin >> p;
	sort(primes.begin(), primes.end());
	
	findSmall(primes);
	
	vector<int> one, two;
	for(int p : primes) {
		if(p <= 17) one.push_back(p);
		else two.push_back(p);
	}
	
	rec(0, 1, one, N, true);
	sort(memo, memo + cnt_memo);
	
	rec(0, 1, two, N, false);
	
	printf("%lld\n", answer);
	cerr << "size = " << cnt_memo << "\n";
}