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#include <cstdio>
#include <algorithm>

using namespace std;

typedef long long ll;

static int primes[100];
static ll divs[100];
static ll n;
static ll best = 0;
static ll* smallend;
static int smallsize;
static ll small[855000];

#define BR 6
static void brute(ll sofar, int i){
	if(i==BR){
		small[smallsize++] = sofar;
		return;
	}
	while(sofar < divs[i]){
		brute(sofar, i+1);
		sofar *= primes[i];
	}
	brute(sofar, i+1);
}

template<int i>
static void solve(ll sofar){
	while(sofar < divs[i]){
		solve<i-1>(sofar);
		sofar *= primes[i];
	}
	solve<i-1>(sofar);
}

template<>
void solve<-1>(ll sofar){
	auto it = upper_bound(small, smallend, n / sofar);
	ll val = sofar * it[-1];
	if(val>best) best = val;
}

int main(){
	int k;
	scanf("%d %lld", &k, &n);
	for(int i=0; i<k; i++){
		int p;
		scanf("%d", &p);
		primes[i] = p;
	}
	sort(primes, primes + k);
	int br = 0;
	if(k < 10){
		small[smallsize++] = 1;
		for(int i=0; i<k; i++){
			divs[i] = n/primes[i]+1;
		}
		smallend = small + smallsize;
	}
	else{
		br = BR;
		swap(primes[br-1], primes[br+1]);
		for(int i=0; i<k; i++){
			divs[i] = n/primes[i]+1;
		}
		brute(1, 0);
		smallend = small + smallsize;
		sort(small, smallend);
	}
	for(int i=0; i<k-br; i++){
		primes[i] = primes[br+i];
		divs[i] = divs[br+i];
	}
	k -= br;
	k--;
	reverse(primes, primes+k);
	reverse(divs, divs+k);

	switch(k){
#define K(i) case i: solve<i>(1); break;
		K(0);
		K(1);
		K(2);
		K(3);
		K(4);
		K(5);
		K(6);
		K(7);
		K(8);
		K(9);
		K(10);
		K(11);
		K(12);
		K(13);
		K(14);
		K(15);
		K(16);
		K(17);
		K(18);
		K(19);
		K(20);
		K(21);
		K(22);
		K(23);
		K(24);
		K(25);
		K(26);
	}
	

	printf("%lld\n", best);
}