#include<cstdio>
#include<cstring>
#include<algorithm>
#define Nmax 105
using namespace std;
int n,k,i,j,v[Nmax],p,m;
int pr[Nmax],sol[Nmax*Nmax];
bool w[Nmax];
void numereprime()
{
    for (i=2;i<=Nmax-5;i++)
    if (!w[i])
    {
        pr[++pr[0]]=i;
        for (j=i*i;j<=Nmax-5;j+=i)
        w[j]=1;
    }
}
void mul(int A[],int B)
{
    int i=0,t=0;
    for (i=1; i<=A[0] || t;++i)
    {
        A[i]=A[i]*B+t;
        t=A[i]/10;
        A[i]=A[i]%10;
    }
    A[0]=i-1;
}
int main()
{
    freopen("factoriale.in","r",stdin);
    freopen("factoriale.out","w",stdout);
    scanf("%d %d",&n,&k);
    for (i=1;i<=n;i++)
    scanf("%d",&v[i]);
    numereprime();
    sol[0]=1; sol[1]=1;
    for (i=1;i<=pr[0];i++)
    {
        p=0;
        for (j=1;j<=n;j++)
        {
            m=v[j];
            while (m>=pr[i])
            {
                p+=m/pr[i];
                m=m/pr[i];
            }
        }
        if (p==0) break;
        if (p%k==0) continue;
        for (j=1;j<=k-(p%k);++j)
        mul(sol,pr[i]);
    }
    for (i=sol[0];i>=1;--i)
    printf("%d",sol[i]);
    return 0;
}