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#include <stdio.h>
#include <algorithm>
#include <math.h>
#include <vector>
#include <cstring>
using namespace std;
const int N=600000;
vector<int>A,B;
int x[110],n,len,pd[110],pre[600100];
long long lim,y[60000],ans,sqrlim,limA[100],limB[100];
void dfs(int k1,long long k2){
	//cout<<"asd "<<k1<<" "<<k2<<endl;
	if (k1>=A.size()){
		if (k2<=N) pre[k2]=k2; else y[++len]=k2; 
		return;
	}
	dfs(k1+1,k2);
	while (k2<=limA[k1]){
		k2*=A[k1]; dfs(k1+1,k2);
	}
}
int tot=0;
void dfs2(int k1,long long k2){
	if (k1>=B.size()){
		long long limnow=lim/k2;
		if (limnow<=N) ans=max(ans,pre[limnow]*k2); 
		else if (limnow<y[1]) ans=max(ans,pre[N]*k2);
		else {
			int where=upper_bound(y+1,y+len+1,limnow)-y-1; //tot++;
			ans=max(ans,y[where]*k2);
		}
		return;
	}
	dfs2(k1+1,k2);
	while (k2<=limB[k1]){
		k2*=B[k1]; dfs2(k1+1,k2); 
	}
}
void solve(){
	memset(pre,0x00,sizeof pre);
	for (int i=0;i<A.size();i++) limA[i]=sqrlim/A[i];
	for (int i=0;i<B.size();i++) limB[i]=lim/B[i]; len=0; tot=0;
	dfs(0,1); sort(y+1,y+len+1); y[len+1]=lim+1;
	for (int i=1;i<=N;i++) pre[i]=max(pre[i-1],pre[i]);
	dfs2(0,1); //cout<<len<<" "<<tot<<endl;
}
int main(){
	scanf("%d%lld",&n,&lim); 
	for (int i=1;i<=n;i++) scanf("%d",&x[i]);
	sqrlim=sqrt(lim);
	sqrlim=max(sqrlim,0ll);
	while (sqrlim*sqrlim<=lim) sqrlim++;
	while (sqrlim*sqrlim>lim) sqrlim--;
	sort(x+1,x+n+1);
	n=unique(x+1,x+n+1)-x-1;
	for (int i=1;i<=n;i++)
		if (i/2%2==0) A.push_back(x[i]);
		else B.push_back(x[i]);
	ans=0;
	solve(); swap(A,B); solve();
	printf("%lld\n",ans);
	return 0;
}