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#undef _GLIBCXX_DEBUG
//#pragma GCC optimize("O3")
#include<iostream>
#include<algorithm>
#include<vector>
#define rep(i,k,n) for(ll i= (ll) k;i< (ll) n;i++)
#define all(v) (v).begin(), (v).end()
#define SZ(v) (int)((v).size())
#define pb push_back
#define ft first
#define sd second
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
const long long INF = 4e18L + 1;
const int IINF = 2e9 + 1;

using namespace std;

template<class TH> void _dbg(const char *sdbg, TH h){ cerr<<sdbg<<'='<<h<<endl; }
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
  while(*sdbg!=',')cerr<<*sdbg++;cerr<<'='<<h<<','; _dbg(sdbg+1, a...);
}

#ifdef LOCAL
#define DBG(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define DBG(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

const int maxtab = 1500000;
ll k, N;
ll sqrtN;
ll tab[25];
ll T[25];
ll kand = 1;

int tryb;
ll maxrek = 0;
int pom[maxtab];
int ile_mam_w_tab;
int ktory_dod;

int wez_ind(ll moj_max)
{
	if (pom[0] > moj_max) return -1;
	int ok = 0, nieok = ile_mam_w_tab;
	while(nieok - ok > 1)
	{
		int sr = (ok + nieok)/2;
		if (pom[sr] <= moj_max) ok = sr;
		else nieok = sr;
	}
	return ok;
}
inline void dodaj(ll co, ll pr)
{
	if (tryb == 2 || tryb == 4)
	{
		if (co <= N)
			kand = max(kand, co);
		if (co > T[pr]*sqrtN || ile_mam_w_tab == 0)
			return;
		ll moj_maks = N/co;
		//int ind = wez_ind(moj_maks);
		int ind = upper_bound(pom, pom+ile_mam_w_tab, moj_maks) - pom - 1;
		if (ind >= 0)
		{
			kand = max(kand, pom[ind] * co);
		}
		return;
	}
	if (co*100ll < sqrtN)
		return;
	if (ktory_dod < maxtab && tryb == 1)
	{
		pom[ktory_dod] = co;
		ile_mam_w_tab++;
	}
	if (ktory_dod >= maxtab && tryb == 3)
	{
		pom[ktory_dod-maxtab] = co;
		ile_mam_w_tab++;
	}
	ktory_dod++;
}

void rek(ll akt_wyn, int ind, int pr = -1)
{
	if (ind == k) return;
	bool pier = true;
	while(akt_wyn <= maxrek)	
	{
		if (!pier)
			dodaj(akt_wyn, pr);
		pier = false;
		rek(akt_wyn, ind+1, pr);
		if (pr == -1) pr = ind;
		akt_wyn *= tab[ind];
	}
}

void rob(int t)
{
	tryb = t;
	if (t == 2 || t == 4)
	{
		maxrek = 10*sqrtN;
		rek(1, 0);
	}
	else
	{
		maxrek = sqrtN;
		ile_mam_w_tab = 0;
		ktory_dod = 0;
		rek(1, 0);
		sort(pom, pom + ile_mam_w_tab);
	}
}

int main()
{
#ifndef LOCAL
    ios_base::sync_with_stdio(0);
    cin.tie(0);
#endif
	cin>>k>>N;
	for(int i=0; i<k; i++)
	{
		cin>>tab[i];
		T[i] = ceil(sqrt((double)tab[i]));
	}
	sort(tab, tab+k);
	sort(T, T+k);
	sqrtN = 0;
	ll skok = 10000;
	while( (sqrtN + skok) * (sqrtN + skok) <= N) sqrtN += skok;
	skok = 1;
	while( (sqrtN + skok) * (sqrtN + skok) <= N) sqrtN += skok;
	rob(1);
	rob(2);
	rob(3);
	rob(4);
	cout << kand;
	
	
	
	return 0;
}