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#include <cstdio>
#include <algorithm>
using namespace std;

typedef long long ll;

const int T = 1000000;
int pr1[] = {2, 3, 5, 7, 11, 13, 17, 89, 97};
int pr2[] = {29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 19, 23};
int p[40], tot;
ll n, ret;
int d, m, num[101000], premax[T + 10];
void dfs1(int d, int x, int y, int v) {
	if (x <= T) premax[x] = x; else num[++tot] = x;
	for (int k = d; k < v; k++) {
		int ny = y / p[k];
		int nx = x;
		while (ny) {
			dfs1(k + 1, nx * p[k], ny, v);
			ny /= p[k];
			nx *= p[k];
		}
	}
}
void dfs2(int d, ll x, ll y, int v) {
	if (y <= T)
		ret = max(ret, premax[y] * x);
	else if (tot > 0)
		ret = max(ret, (*(upper_bound(num, num + tot, y) - 1)) * x);
	for (int k = d; k < v; k++) {
		ll ny = y / p[k];
		ll nx = x;
		while (ny) {
			dfs2(k + 1, nx * p[k], ny, v);
			ny /= p[k];
			nx *= p[k];
		}
	}
}
int mark[110], k, k1, k2, x;
void init() {
	scanf("%d%lld", &k, &n);
	for (int i = 0; i < k; i++) {
		scanf("%d", &x);
		mark[x] = 1;
	}
	for (int i = 0; i < 9; i++)
		if (mark[pr1[i]]) p[k1++] = pr1[i];
	k2 = k1;
	for (int i = 0; i < 16; i++)
		if (mark[pr2[i]]) p[k2++] = pr2[i];
}

int main() {
	init();
	m = 1000000000;

	tot = 0;
	for (int i = 1; i <= T; i++) premax[i] = 0;
	dfs1(0, 1, m, k1);
	for (int i = 1; i <= T; i++)
		premax[i] = max(premax[i], premax[i - 1]);
	sort(num, num + tot);
	dfs2(k1, 1, n, k2);

	tot = 0;
	for (int i = 1; i <= T; i++) premax[i] = 0;
	dfs1(k1, 1, m, k2);
	for (int i = 1; i <= T; i++)
		premax[i] = max(premax[i], premax[i - 1]);
	sort(num, num + tot);
	dfs2(0, 1, n, k1);

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