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// Krzysztof Małysa
#include <bits/stdc++.h>
using namespace std;

#define FOR(i,a,n) for (auto i = (a), i ## __ = (n); i <= i ## __; ++i)
#define FORD(i,a,n) for (auto i = (a), i ## __ = (n); i >= i ## __; --i)
#define REP(i,n) FOR(i, 0, n - 1)
#define ALL(x) x.begin(), x.end()
#define SZ(x) (int(x.size()))
#define EB emplace_back
#define ST first
#define ND second
#define tpv typedef vector<

typedef long long LL;
typedef pair<int, int> PII;
tpv int> VI;
tpv VI> VVI;
tpv PII> VPII;
tpv LL> VLL;

constexpr char nl = '\n';
#define endl nl

#define ris return *this
#define tem template<class T

tem, class B> inline void mini(T&& a, B&& b) { if (b < a) a = b; }
tem, class B> inline void maxi(T&& a, B&& b) { if (b > a) a = b; }
int ceil2(int x) { return x < 2 ? 1 : 1 << (sizeof(x) * 8 - __builtin_clz(x - 1)); }

tem> struct Dump { T a, b; };
tem> auto dump(T&& x) -> Dump<decltype(x.begin())> { return {ALL(x)}; }
struct Debug {
	~Debug() { cerr << endl; }
	tem> auto operator<<(T x) -> decltype(cerr << x, *this) { cerr << boolalpha << x; return *this; }
	tem> auto operator<<(T x) -> decltype(x.begin(), *this) {
		auto a = x.begin(), b = x.end();
		*this << "{";
		for (; a != b;)
			*this << *a++, *this << (a == b ? "" : " ");
		return *this << "}";
	}
	tem, class B> Debug& operator<<(pair<T, B> p) { ris << "(" << p.ST << ", " << p.ND << ")"; }
	tem> Debug& operator<<(Dump<T> d) {
		*this << "{\n";
		for (T a = d.a, c = a; a != d.b; ++a)
			*this << "  " << distance(c, a) << ": " << *a << '\n';
		ris << "}";
	}
};
struct Foo {tem>Foo& operator<<(T) {ris;}};

#ifdef DEBUG
# define deb Debug()
#else
# define deb Foo()
#endif
#define imie(x...) #x ": " << (x) << " "
#define LOG(x...) deb << imie(x)
#define DOG(x...) deb << #x ": " << dump(x) << " "

template<class I>
void inplace_sort(I a, I b) {
	make_heap(a, b);
	sort_heap(a, b);
}

LL n;

void span(VLL& S, VI primes) {
	// This way to preserve reserve() xd
	S.resize(1);
	S[0] = 1;

	// Fill S
	for (int p : primes) {
		int sz = SZ(S);
		for (LL a = p; a < n; a *= p) {
			REP (i, sz) {
				if (S[i] > n / a)
					break;
				S.EB(S[i] * a);
			}
			// Prevents long long overflow
			if (a > n / p)
				break;
		}

		// sort(ALL(S));
		inplace_sort(ALL(S));
	}
}

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

	int k;
	cin >> k >> n;
	VLL S1, S2, S3;
	S1 = S2 = S3 = {1};

	VI primes(k);
	for (int& x : primes)
		cin >> x;
	sort(ALL(primes));

	auto extract_l_elems = [&](int l) {
		mini(l, SZ(primes));
		VI res(primes.begin(), primes.begin() + l);
		primes.erase(primes.begin(), primes.begin() + l);
		return res;
	};

	// First 5 elements
	S1.reserve(276997);
	VI p1 = extract_l_elems(5);
	span(S1, p1);

	// Next 8 elements
	S2.reserve(167288);
	VI p2 = extract_l_elems(8);
	span(S2, p2);

	// Last 12 elements
	S3.reserve(396247);
	VI p3 = extract_l_elems(12);
	span(S3, p3);

	LOG(p1);
	LOG(p2);
	LOG(p3);
	LOG(SZ(S1));
	LOG(SZ(S2));
	LOG(SZ(S3));

	LL res = 1;
	// Meet in the middle S2 and S3 and binsearch in S1
	for (LL x : S2) {
		LL boundary = n / x;
		for (LL y : S3) {
			if (y > boundary)
				break;

			LL e = x * y; // Element
			maxi(res, e);
			maxi(res, e * *--upper_bound(ALL(S1), n / e));
		}
	}

	cout << res << nl;

	return 0;
}