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#include<bits/stdc++.h>
#define rep(i,k,n) for(ll i= (ll) k;i< (ll) n;i++)
#define all(v) (v).begin(), (v).end()
#define SZ(v) (int)((v).size())
#define pb push_back
#define ft first
#define sd second
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
const long long INF = 1e18L + 1;
const int IINF = 1e9 + 1;

using namespace std;

template<class TH> void _dbg(const char *sdbg, TH h){ cerr<<sdbg<<'='<<h<<endl; }
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
  while(*sdbg!=',')cerr<<*sdbg++;cerr<<'='<<h<<','; _dbg(sdbg+1, a...);
}

#ifdef LOCAL
#define DBG(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define DBG(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

vector<ll> prms;

const int N = 5e5;

int lst[N + 1];
bool has_two = false;

ll solve(ll n, ll i){
	if(n <= N){
		return lst[n];
	}
	ll res = (has_two) ? 1ll << (63ll - __builtin_clzll(n)) : 1ll;
	rep(j, i, SZ(prms)){
		if(n >= prms[j]){
			res = max(res, prms[j] * solve(n / prms[j], j));	
		}
	}
	return res;
}

int main()
{
#ifndef LOCAL
	ios_base::sync_with_stdio(0);
    cin.tie(0);
#endif
	ll pcnt, n; cin >> pcnt >> n;
	rep(_, 0, pcnt){
		int t1; cin >> t1;
		if(t1 == 2){
			has_two = true;
		} else {
			prms.pb(t1);
		}
	}
		
	rep(i, 1, N + 1){
		lst[i] = i;
	}
	for(auto& p : prms){
		for(int k = 1; k * p <= N; k++){
			while(lst[k * p] % p == 0){
				lst[k * p] /= p;
			}
		}
	}
	if(has_two){
		rep(i, 1, N + 1){
			lst[i] /= (1ll << __builtin_ctz(i));
		}
	}
	rep(i, 2, N + 1){
		if(lst[i] == 1){
			lst[i] = i;
		} else{
			lst[i] = lst[i - 1];
		}
	}

	cout << solve(n, 0) << "\n";
    return 0;
}