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#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <vector>
#include <set>
#include <map>
#include <cmath>
#include <list>
#include <ctime>
#include <sstream>
#include <queue>
#include <stack>
#include <bitset>
#include <unordered_set>
#include <unordered_map>
#include <climits>
using namespace std;
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef unsigned long long ll;
typedef short int sint;
#define FOR(x, b, e) for(int x=(b); x<=(e); ++x)
#define FORD(x, b, e) for(int x=((int)(b))-1; x>=(e); --x)
#define REP(x, n) for(int x=0; x<(n); ++x)
#define ALL(c) c.begin(),c.end()
#define SIZE(x) ((int)((x).size()))
#define PB push_back
#define ST first
#define ND second
#define mp(x,y) make_pair(x,y)
#define DEBUG 1
#define debug(x) {if (DEBUG)cerr <<#x <<" = " <<x <<endl; }
#define debugv(x) {if (DEBUG) {cerr <<#x <<" = "; FOREACH(it, (x)) cerr <<*it <<", "; cout <<endl; }}
#define REMAX(a,b) (a)=max((a),(b));
#define REMIN(a,b) (a)=min((a),(b));
#define wez(n) int (n); scanf("%d",&(n));
#define wez2(n,m) int (n),(m); scanf("%d %d",&(n),&(m));

const int K = 25;
const ll inf = 1000000000000000000LL;
const int MAXN = 950000;
const ll lowLimit = 64 * MAXN;
int a[K];
ll wys[MAXN];
int k, ile;
ll n;
// ll zb[MAXN];
ll bestRes = 1;
ll limit, biggest;
ll drug = 0;

bool shouldSave;

inline pair<ll, ll> rep(ll x) {
	return mp(x >> 6, x &63LL);
}

inline void add(ll x) {
	auto pom = rep(x);
	wys[pom.ST] |= (1LL << pom.ND);
	// if (x == 1200506) printf("adding: %llu, pos: %llu, wys[%llu] = %llu\n", x, pom.ST, pom.ND, wys[pom.ST]);
}

inline ll find(ll x) {
	if (x >= lowLimit) {
		return biggest;
	}
	// printf("finding for: %llu\n", x);
	auto pom = rep(x);
	ll box = wys[pom.ST];
	// printf("\trep: %llu, %llu\n", pom.ST, pom.ND);
	if (pom.ND != 63) {
		box = box & ((1LL << (pom.ND + 1)) - 1);
	}
	while (true) {
		// printf("\t\tbox: %llu\n", box);
		if (box != 0) {
			int pos = __builtin_clzll(box);
			// printf("pos: %d\n", pos);
			return (pom.ST << 6) + (63 - pos);
		}
		--pom.ST;
		// printf("\tgoing back\n");
		box = wys[pom.ST];
	}
	
}

// inline ll bin_search(ll szuk) {
// 	int p = ile;
// 	if (szuk > zb[ile - 1]) {
// 		p = ile;
// 	} else {
// 		p = upper_bound(zb, zb + ile, szuk) - zb;
// 	}
// 	return zb[p - 1];
// }

inline bool canMult(ll a, ll b) {
	return !(b > (2 * inf / a));
}

void generuj(int pos = 0, ll ilo = 1) {
	// printf("generuj: %lld, %d, %lld\n", limit, pos, ilo);
	if (pos == k) {
		if (shouldSave) {
			// zb[ile++] = ilo;
			if (ilo > biggest) {
				biggest = ilo;
			}
			if (ilo > bestRes && ilo <= n) {
				bestRes = ilo;
			}
			add(ilo);
		} else {
			++drug;
			ll szuk = n / ilo;
			
			// ll val = bin_search(szuk);
			ll val = find(szuk);
			// if (val != other) {
			// 	printf("looking for: %llu, bin: %llu, val: %llu\n", szuk, val, other);
			// 	return ;
			// }
			if (canMult(val, ilo)) {
				ll kand = val * ilo;
				if (kand > bestRes && kand <= n) {
					bestRes = kand;
				}
			}
		}
		return;
	}
	generuj(pos + 1, ilo);
	while (canMult(a[pos], ilo) && (ilo * a[pos]) <= limit) {
		ilo *= a[pos];
		generuj(pos + 1, ilo);
	}
}

int main() {
	scanf("%d %llu", &k, &n);
	REP(i, k) {
		scanf("%d", &a[i]);
	}
	shouldSave = true;
	limit = lowLimit - 1;
	generuj();
	// printf("ile: %d\n", ile);
	// sort(zb, zb + ile);
	if (n <= limit) {
		cout << bestRes << endl;
		return 0;
	}
	shouldSave = false;
	limit = n / limit * 97;
	// printf("upper limit: %llu\n", limit);
	generuj();
	// printf("wygenerowalo: %llu\n", drug);
	cout << bestRes << endl;
	return 0;
}