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#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<vector>
#include<cmath>
#include<iostream>

using namespace std;

#define PB push_back
#define MP make_pair
#define F first
#define S second
#define ALL(x) (x).begin(),(x).end()
#define SIZE(x) (int)(x).size()
#define SORT(x) sort((x).begin(),(x).end())
#define CLEAR(tab) memset(tab, 0, sizeof(tab))
#define REP(x, n) for(int x = 0; x < (n); x++)
#define FOR(x, b, e) for(int x = (b); x <= (e); x++)
#define FORD(x, b, e) for(int x = (b); x >= (e); x--)
#define VAR(v, n) __typeof(n) v = (n)
#define FOREACH(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define DEBUG(fmt, ...) fprintf(stderr, fmt, ##__VA_ARGS__)

const int MAX_BUF_SIZE = 16384;
char BUFOR[MAX_BUF_SIZE];
int BUF_SIZE, BUF_POS;
char ZZZ;
#define GET(ZZZ){ZZZ='a';if(BUF_POS<BUF_SIZE)ZZZ=BUFOR[BUF_POS++];\
else if(!feof(stdin)){BUF_SIZE=fread(BUFOR,1,MAX_BUF_SIZE,stdin);\
ZZZ=BUFOR[0];BUF_POS=1;}}
#define GI(WW){do{GET(ZZZ);}while(!isdigit(ZZZ));WW=ZZZ-'0';\
while(1){GET(ZZZ);if(!isdigit(ZZZ))break;WW=WW*10+(ZZZ-'0');}}
#define GC(WW){do{GET(ZZZ);}while(!isalpha(ZZZ));WW=ZZZ;}

//FAST IO

typedef long long int LL;
typedef pair<int,int> PII;
typedef vector<int> VI;

const int MXN = 1000010;
const int C = 1000000;
const LL INF = 1000000000000000000LL;
const int D = 4 * 1000000;

LL cnt;
VI primes;
VI vec;
LL MX;
LL KK;

int w;

void check(LL x, LL K) {
    int L = 0, R = SIZE(vec) - 1;
    while(L <= R) {
        int S = (L + R) / 2;
        LL yy = (LL)vec[S] * vec[S];
        if(yy <= K / x) {
            MX = max(MX, x * yy);
            L = S + 1;
        }
        else {
            R = S - 1;
        }
    }
}

void gen(LL iloczyn, int k, LL K) {
    if(iloczyn < 0)
        return;
    if(k == SIZE(primes) ) {
        check(iloczyn, KK);
        return;
    }
    int pot = 1;
    int q = primes[k];
    int w = 0;
    while(w <= 1) {
        if(iloczyn <= K / pot)
            gen(iloczyn * pot, k + 1, K);
        else
            break;
        pot = pot * q;
        w++;
    }
}

void gen2(LL iloczyn, int k, LL K) {
    if(k >= SIZE(primes) ) {
        vec.PB(iloczyn);
        if(SIZE(vec) == C) {
            SORT(vec);
            gen(1, 0, D);
            vec.clear();
        }
        return;
    }
    LL pot = 1;
    int q = primes[k];
    while(pot <= K) {
        if(iloczyn * pot <= K)
            gen2(iloczyn * pot, k + 1, K);
        else
            break;
        pot = pot * q;
    }
}

vector<int> T;

void gen3(LL iloczyn, int k, LL K) {
    if(iloczyn < 0)
        return;
    if(k == SIZE(primes) ) {
        if(iloczyn >= D) {
            int tmp = sqrt(KK / iloczyn);

            LL yy = (LL)T[tmp] * T[tmp];
            if(yy <= KK / iloczyn)
                MX = max(MX, (LL)yy * iloczyn);
            //iloczyn * T[sqrt(KK / D]
        }
        return;
    }
    int pot = 1;
    int q = primes[k];
    int w = 0;
    while(w <= 1) {
        if(iloczyn <= K / pot)
            gen3(iloczyn * pot, k + 1, K);
        else
            break;
        pot = pot * q;
        w++;
    }
}

void maleX() {
    gen2(1, 0, min(KK, 1000000000LL) );
    if(SIZE(vec) > 0) {
        SORT(vec);
        gen(1, 0, D);
        vec.clear();
    }
}

void duzeX() {
    int ogr = sqrt(KK / D);
    gen2(1, 0, ogr);
    FOR(i, 0, ogr)
        T.PB(0);
    int j = 1;
    T[0] = T[1] = 1;
    FOREACH(it, vec)
        T[*it] = *it;
    FOR(i, 1, ogr)
        if(T[i] == 0)
            T[i] = T[i - 1];
    gen3(1, 0, KK);
}

int main() {
    int n;
    LL k;
    scanf("%d %lld", &n, &k);
    KK = k;
    FOR(i, 1, n) {
        int x;
        scanf("%d", &x);
        primes.PB(x);
    }

    maleX();
    duzeX();

	printf("%lld\n", MX);
	return 0;
}