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#include <bits/stdc++.h>

using namespace std;

typedef long long int LL;

const int N = 2e5 + 9;

LL n, n2;
LL result = 0LL;

int cnt;
LL tab[N];

int k;
int pm, stop;
int primes[30];

inline LL kwa(LL a){
	return a * a;
}

LL find(LL x){
	if(tab[1] > x)
		return 1LL;

	int p = 1, k = cnt;
	while(p < k){
		int m = (p + k + 1) >> 1;
		if(tab[m] <= x)
			p = m;
		else
			k = m - 1;
	}
	
	return tab[p];
}

void add(int cur, int m){
	if(cur == stop)
		return;
	
	if(1LL * m * primes[cur] <= n2){
		add(cur, m * primes[cur]);
		tab[++cnt] = 1LL * m * primes[cur] * pm;
		add(cur + 1, m);
	}
}

void check(int cur, int m){
	if(cur == stop)
		return;
	
	if(1LL * m * primes[cur] <= n2){
		check(cur, m * primes[cur]);
		if(1LL * m * primes[cur] * pm >= n2)
			result = max(result, 1LL * m * primes[cur] * find(n / (1LL * m * primes[cur])));
		check(cur + 1, m);
	}
}

int main(){
	scanf("%d %lld", &k, &n);
	for(int i = 0; i < k; ++i)
		scanf("%d", &primes[i]);
	sort(primes, primes + k);
	
	n2 = sqrt(n);
	while(kwa(n2 + 1) <= n)
		++n2;
	while(kwa(n2) > n)
		--n2;

	for(int i = 0; i < k; ++i){
		tab[1] = 1;
		cnt = 1; pm = primes[i];

		if(i < 9){
			stop = i + 1;
			add(0, 1);
		}
		else{
			stop = k;
			add(i, 1);
		}
		
		tab[1] *= pm;
		sort(tab + 1, tab + cnt + 1);
		
		if(i < 9){
			stop = k;
			check(i, 1);
		}
		else{
			stop = i + 1;
			check(0, 1);
		}
		
		result = max(result, find(n));
	}

	printf("%lld\n", result);
 	return 0;
}