#include <iostream>
#include <fstream>
#include <vector>
 
std::ifstream f("factoriale.in");
std::ofstream g("factoriale.out");
 
const int NMAX = 120;
const int SIZE = 1000002;
std::vector<int>primes{2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97};
long long n,k,v[NMAX],fr[NMAX],sol[SIZE];
 
void update(int nr){
    
    for(int i = 0;i < primes.size();++i){
        
        while(nr % primes[i] == 0 && nr > 1){
            fr[primes[i]]++;
            nr /= primes[i];
        }
        
        if(nr == 1)
            return;
        
        if(primes[i] > nr && nr != 1){
            fr[nr]++;
            return;
        }
        
    }
    
    //if(nr != 1)
      //  fr[nr]++;
}
 
void multiply(long long *sol,int value){
    
    int t{};
    for(int i = 1;i <= sol[0];++i){
        sol[i] = sol[i] * value + t;
        t = (int)sol[i] / 10LL;
        sol[i] %= 10;
    }
    
    if(t)
        sol[++sol[0]] = t;
}
 
int main(){
    
    f >> n >> k;
    
    for(int i = 1;i <= n;++i){
        
        f >> v[i];
        
        for(int j = 2;j <= v[i];++j)
            update(j);
    }
    
    sol[0] = sol[1] = 1;
    
    for(int i = 2;i <= 100;++i)
        if(fr[primes[i]] != 0 && fr[primes[i]] % k != 0)
            for(int j = 1;j <= k - (fr[primes[i]] % k) ;++j)
                multiply(sol,primes[i]);
    
    for(int i = (int)sol[0];i >= 1;--i)
        g << sol[i];
    
    return 0;
}