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

const int MAX_POT = 65;
const long long INF = 2 * 1e18;
vector<long long> prime;
vector<vector<long long> > pot;
long long n, result;
int k;

void read() {
    scanf("%d%lld", &k, &n);
    for(int i = 0; i < k; ++i) {
        long long p;
        scanf("%lld", &p);
        prime.push_back(p);
    }
}

void prepare() {
    pot.resize(k);
    for(int i = 0; i < k; ++i) {
        pot[i].resize(MAX_POT, 1LL);
    }

    for(int i = 0; i < k; ++i) {
        long long p = prime[i], power = p, limit = INF / p;
        for(int j = 1; j < MAX_POT; ++j) {
            pot[i][j] = power;
            if(power < limit)
                power *= p;
            else
                power = INF;
        }
    }
}

void solve(long long number, int it) {
    long long limit = INF / number;

    if(it == k - 1) {
        int L = 0, P = MAX_POT;
        while(L + 1 < P) {
            int mid = (L + P) / 2;
            long long power = pot[it][mid];
            if(power < limit and number * power <= n)
                L = mid;
            else
                P = mid;
        }
        result = max(result, number * pot[it][L]);

        return;
    }

    for(int i = 0; i < MAX_POT; ++i) {
        long long power = pot[it][i];
        if(power < limit and power * number <= n)
            solve(number * power, it + 1);
        else
            break;
    }
}

int main()
{
    read();
    prepare();
    solve(1LL, 0);
    printf("%lld", result);

    return 0;
}