#include <iostream>
#include <fstream>
using namespace std;
ifstream f("factoriale.in");
ofstream g("factoriale.out");
int n,k,prim[101],nr,x[101];bool ciur[101];
void ce()
{
    int i,j;
    prim[++nr]=2;
    for(i=3;i<=100;i+=2)
        if(ciur[i]==0)
    {
        prim[++nr]=i;
        for(j=i*2;j<=100;j+=i)
            ciur[j]=1;
    }
}
int sol[50001],nrcif=1;
void produs(int a)
{
    int i,t=0;
    for(i=1;i<=nrcif;i++)
    {
        sol[i]=sol[i]*a+t;
        t=sol[i]/10;
        sol[i]%=10;
    }
    while(t!=0)
    {
        nrcif++;
        sol[nrcif]=t%10;;
        t=/10;
    }
}
void solve()
{
    f>>n>>k; int i,a,j,k1,z;
    for(i=1;i<=n;i++)
    {
        f>>a;
        for(k1=2;k1<=a;k1++){z=k1; for(j=1;j<=nr&&z>1;j++)while(z%prim[j]==0){x[j]++; z/=prim[j];} }
    }
    sol[1]=1;
    for(i=1;i<=nr;i++)if(x[i]%k!=0) produs((k-x[i]%k)*prim[i]);
}
void write()
{
    int i;
    for(i=nrcif;i>=1;i--)g<<sol[i];
}
int main()
{
    ce();solve();write();
    return 0;
}